[main/WARN] [FML]: The coremod SpongeCoremod (org.spongepowered.mod.SpongeCoremod) is not signed!

server crashing evry timei luanch it

[16:00:39] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
[16:00:39] [main/INFO] [LaunchWrapper]: Using primary tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
[16:00:39] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLServerTweaker
[16:00:39] [main/INFO] [FML]: Forge Mod Loader version 14.23.5.2838 for Minecraft 1.12.2 loading
[16:00:39] [main/INFO] [FML]: Java is Java HotSpot™ 64-Bit Server VM, version 1.8.0_271, running on Windows 10:amd64:10.0, installed at C:\Program Files\Java\jre1.8.0_271
[16:00:39] [main/INFO] [FML]: Searching C:\Users\mathi\Desktop\Pixelmmon.\mods for mods
[16:00:39] [main/INFO] [FML]: Loading tweaker org.spongepowered.asm.launch.MixinTweaker from spongeforge-1.12.2-2838-7.3.1-RC4093.jar
[16:00:39] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[16:00:39] [main/INFO] [LaunchWrapper]: Loading tweak class name org.spongepowered.asm.launch.MixinTweaker
[16:00:39] [main/INFO] [mixin]: SpongePowered MIXIN Subsystem Version=0.8 Source=file:/C:/Users/mathi/Desktop/Pixelmmon/./mods/spongeforge-1.12.2-2838-7.3.1-RC4093.jar Service=LaunchWrapper Env=SERVER
[16:00:39] [main/WARN] [FML]: The coremod SpongeCoremod (org.spongepowered.mod.SpongeCoremod) is not signed!
[16:00:39] [main/INFO] [mixin]: Compatibility level set to JAVA_8
[16:00:40] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[16:00:40] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[16:00:40] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[16:00:40] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[16:00:41] [main/INFO] [FML]: Found valid fingerprint for Minecraft Forge. Certificate fingerprint e3c3d50c7c986df74c645c0ac54639741c90a557
[16:00:41] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[16:00:41] [main/INFO] [LaunchWrapper]: Calling tweak class org.spongepowered.asm.launch.MixinTweaker
[16:00:41] [main/INFO] [mixin]: Initialised Mixin FML Remapper Adapter with net.minecraftforge.fml.common.asm.transformers.deobf.FMLDeobfuscatingRemapper@105b693d
[16:00:41] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[16:00:41] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.TerminalTweaker
[16:00:41] [main/INFO] [LaunchWrapper]: Loading tweak class name org.spongepowered.asm.mixin.EnvironmentStateTweaker
[16:00:41] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.TerminalTweaker
[16:00:41] [main/INFO] [LaunchWrapper]: Calling tweak class org.spongepowered.asm.mixin.EnvironmentStateTweaker
[16:00:42] [main/WARN] [mixin]: @Mixin target net/minecraft/block/state/BlockStateContainer$StateImplementation is public in mixins.common.api.json:mcp.block.state.StateImplementationMixin_API and should be specified in value
[16:00:44] [main/WARN] [mixin]: @Mixin target net/minecraft/server/management/PlayerProfileCache$ProfileEntry is public in mixins.common.core.json:server.management.PlayerProfileCache_ProfileEntryAccessor and should be specified in value
[16:00:45] [main/INFO] [mixin]: Instancing error handler class org.spongepowered.mod.mixin.handler.MixinErrorHandler
[16:00:45] [main/INFO] [Sponge]: //
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
Oh dear. Something went wrong and the server had to shut down! /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
/
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
A critical error was encountered while blending Sponge with Forge! /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
Possible causes are: /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
* An incompatible Forge “core mod” is present. Try removing other mods to /
[16:00:45] [main/INFO] [Sponge]: /
see if the problem goes away. /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
* You are using the wrong version of Minecraft Forge. You must use the /
[16:00:45] [main/INFO] [Sponge]: /
correct version of Forge when running Sponge, this version is for /
[16:00:45] [main/INFO] [Sponge]: /
14.23.5.2838 (you are running 14.23.5.2838) /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
* An error exists in Sponge itself. Ensure you are running the latest version /
[16:00:45] [main/INFO] [Sponge]: /
of Sponge. /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
* Gremlins are invading your computer. Did you feed a Mogwai after midnight? /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
/
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
Technical details: /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
Failed on class : net.minecraft.server.MinecraftServer /
[16:00:45] [main/INFO] [Sponge]: /
During phase : DEFAULT /
[16:00:45] [main/INFO] [Sponge]: /
Mixin : server.MinecraftServerMixin_Forge /
[16:00:45] [main/INFO] [Sponge]: /
Config : mixins.forge.core.json /
[16:00:45] [main/INFO] [Sponge]: /
Error Type : org.spongepowered.asm.mixin.transformer.throwables.InvalidMixinException /
[16:00:45] [main/INFO] [Sponge]: /
Caused by : Unknown /
[16:00:45] [main/INFO] [Sponge]: /
Message : @Shadow method getPlayerProfileCache in mixins.forge.core.json:server.MinecraftServerMixin_Forge was not located in the target class net.minecraft.server.MinecraftServer. Using refmap mixins.forge.refmap.json /
[16:00:45] [main/INFO] [Sponge]: /
/
[16:00:45] [main/INFO] [Sponge]: /
****/
Press any key to continue . . .

The error of it not being signed is fine.

The issue is that your using the dev builds. Try the recommended build

28.10 22:09:04 [Server] Server thread/INFO Osius joined the game
28.10 22:09:09 [Connect] User Osius, IP unknown
28.10 22:09:09 [Multicraft] Osius ran command Message of the Day
28.10 22:10:10 [Disconnect] User Osius has disconnected, reason: Disconnected
28.10 22:10:10 [Server] Server thread/INFO Osius left the game
28.10 22:18:04 [Multicraft] Auto-saving world…
28.10 22:18:04 [Server] Server thread/INFO Saving is already turned on
28.10 22:18:04 [Server] Server thread/INFO Saving…
28.10 22:18:04 [Server] Server thread/INFO [Server] World saved.
28.10 22:28:10 [Multicraft] Auto-saving world…
28.10 22:28:10 [Server] Server thread/INFO Saving is already turned on
28.10 22:28:10 [Server] Server thread/INFO Saving…
28.10 22:28:10 [Server] Server thread/INFO [Server] World saved.
28.10 22:38:16 [Multicraft] Auto-saving world…
28.10 22:38:16 [Server] Server thread/INFO Saving is already turned on
28.10 22:38:16 [Server] Server thread/INFO Saving…
28.10 22:38:16 [Server] Server thread/INFO [Server] World saved.
28.10 22:46:42 [Multicraft] Received restart command
28.10 22:46:42 [Multicraft] Stopping server!
28.10 22:46:42 [Server] Server thread/INFO Saving…
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: java.io.FileNotFoundException: ./world/session.lock (No such file or directory)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at java.io.FileOutputStream.open0(Native Method)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at java.io.FileOutputStream.open(FileOutputStream.java:270)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at java.io.FileOutputStream.(FileOutputStream.java:213)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at java.io.FileOutputStream.(FileOutputStream.java:162)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.storage.SaveHandler.func_75766_h(SaveHandler.java:62)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.storage.SaveHandler.redirect$zmm000$impl$createSessionLockAndCreateDirectories(SaveHandler.java:1126)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.storage.SaveHandler.func_75762_c(SaveHandler.java:90)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.World.func_72906_B(World.java:3489)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.WorldServer.func_73042_a(WorldServer.java:1032)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.world.WorldServer.func_73044_a(WorldServer.java:4277)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.command.server.CommandSaveAll.func_184881_a(SourceFile:41)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.command.CommandHandler.func_175786_a(CommandHandler.java:119)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.command.CommandHandler.accessor$tryExecuteCommand(CommandHandler.java)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at org.spongepowered.common.command.MinecraftCommandWrapper.tryExecute(MinecraftCommandWrapper.java:161)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at org.spongepowered.common.command.MinecraftCommandWrapper.process(MinecraftCommandWrapper.java:146)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at org.spongepowered.common.command.SpongeCommandDispatcher.process(SpongeCommandDispatcher.java:355)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at org.spongepowered.common.command.SpongeCommandManager.process(SpongeCommandManager.java:360)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.command.ServerCommandManager.func_71556_a(SourceFile:665)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.server.dedicated.DedicatedServer.func_71333_ah(DedicatedServer.java:433)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:398)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
28.10 22:46:42 [Server] Server thread/INFO [STDERR]: [net.minecraft.world.storage.SaveHandler:func_75766_h:75]: at java.lang.Thread.run(Thread.java:748)
28.10 22:46:42 [Server] Server thread/INFO Error occurred while executing command: java.lang.RuntimeException: Failed to check session lock, aborting
28.10 22:46:42 [Server] Server thread/ERROR [Sponge]: Error occurred while executing command ‘save-all’ for source DedicatedServer: java.lang.RuntimeException: Failed to check session lock, aborting
28.10 22:46:42 [Server] INFO java.lang.RuntimeException: java.lang.RuntimeException: Failed to check session lock, aborting
28.10 22:46:42 [Server] INFO at org.spongepowered.common.command.MinecraftCommandWrapper.tryExecute(MinecraftCommandWrapper.java:165) ~[MinecraftCommandWrapper.class:1.12.2-2838-7.3.1-RC4082]
28.10 22:46:42 [Server] INFO at org.spongepowered.common.command.MinecraftCommandWrapper.process(MinecraftCommandWrapper.java:146) ~[MinecraftCommandWrapper.class:1.12.2-2838-7.3.1-RC4082]
28.10 22:46:43 [Multicraft] Server shut down (stopping)
28.10 22:46:43 [Multicraft] Server stopped
28.10 22:46:46 [Multicraft] Loading server properties
28.10 22:46:46 [Multicraft] Starting server!
28.10 22:46:46 [Multicraft] Loaded config for “Custom.jar (Use and upload your own JAR)”
28.10 22:46:46 [Multicraft] Updating eula.txt file
28.10 22:46:49 [Server] INFO 2021-10-28 22:46:49,531 main WARN Disabling terminal, you’re running in an unsupported environment.
28.10 22:46:49 [Server] main/INFO [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
28.10 22:46:49 [Server] main/INFO [LaunchWrapper]: Using primary tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
28.10 22:46:49 [Server] main/INFO [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLServerTweaker
28.10 22:46:49 [Server] main/INFO [FML]: Forge Mod Loader version 14.23.5.2855 for Minecraft 1.12.2 loading
28.10 22:46:49 [Server] main/INFO [FML]: Java is OpenJDK 64-Bit Server VM, version 1.8.0_292, running on Linux:amd64:4.15.0-55-generic, installed at /usr/lib/jvm/java-8-openjdk-amd64/jre
28.10 22:46:50 [Server] main/INFO [FML]: Searching /./mods for mods
28.10 22:46:50 [Server] main/INFO [FML]: Searching /./mods/1.12.2 for mods
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in AppleCore-mc1.12.2-3.2.0.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod AppleCore (squeek.applecore.AppleCore) is not signed!
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in astralsorcery-1.12.2-1.10.23.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod hellfirepvp.astralsorcery.core.AstralCore does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/INFO [Astral Core]: [AstralCore] Initialized.
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in Bloodmoon-MC1.12.2-1.5.3.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod lumien.bloodmoon.asm.LoadingPlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in Blur-1.0.4-14.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod com.tterrag.blur.BlurPlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: The coremod BlurPlugin (com.tterrag.blur.BlurPlugin) is not signed!
28.10 22:46:50 [Server] main/INFO [FML]: Loading tweaker codechicken.asm.internal.Tweaker from ChickenASM-1.12-1.0.2.7.jar
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in CreativeCore_v1.10.13_mc1.12.2.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod com.creativemd.creativecore.core.CreativePatchingLoader does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: The coremod CreativePatchingLoader (com.creativemd.creativecore.core.CreativePatchingLoader) is not signed!
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in CTM-MC1.12.2-1.0.2.31.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod team.chisel.ctm.client.asm.CTMCorePlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: The coremod CTMCorePlugin (team.chisel.ctm.client.asm.CTMCorePlugin) is not signed!
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in foamfix-0.10.10-1.12.2.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod pl.asie.foamfix.coremod.FoamFixCore does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: Found FMLCorePluginContainsFMLMod marker in Forgelin-1.8.4.jar. This is not recommended, @Mods should be in a separate jar from the coremod.
28.10 22:46:50 [Server] main/WARN [FML]: The coremod net.shadowfacts.forgelin.preloader.ForgelinPlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: The coremod ForgelinPlugin (net.shadowfacts.forgelin.preloader.ForgelinPlugin) is not signed!
28.10 22:46:50 [Multicraft] Skipped 21 lines due to rate limit (30/s)
28.10 22:46:50 [Server] main/INFO [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
28.10 22:46:50 [Server] main/INFO [LaunchWrapper]: Loading tweak class name codechicken.asm.internal.Tweaker
28.10 22:46:50 [Server] main/INFO [LaunchWrapper]: Loading tweak class name org.spongepowered.asm.launch.MixinTweaker
28.10 22:46:50 [Server] main/ERROR [mixin]: Catching
28.10 22:46:50 [Server] INFO org.spongepowered.asm.service.ServiceInitialisationException: ModLauncher is not available
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.service.modlauncher.MixinServiceModLauncherBootstrap.bootstrap(MixinServiceModLauncherBootstrap.java:52) ~[spongeforge-1.12.2-2838-7.3.1-RC4082.jar:1.12.2-2838-7.3.1-RC4082]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.service.MixinService.runBootServices(MixinService.java:79) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.service.MixinService.(MixinService.java:72) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.service.MixinService.getInstance(MixinService.java:92) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.service.MixinService.boot(MixinService.java:102) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.launch.MixinBootstrap.(MixinBootstrap.java:76) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at org.spongepowered.asm.launch.MixinTweaker.(MixinTweaker.java:44) [malisiscore-1.12.2-6.5.1.jar:1.12.2-6.5.1-SNAPSHOT]
28.10 22:46:50 [Server] INFO at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_292]
28.10 22:46:50 [Server] INFO at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) [?:1.8.0_292]
28.10 22:46:50 [Server] INFO at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) [?:1.8.0_292]
28.10 22:46:50 [Server] INFO at java.lang.reflect.Constructor.newInstance(Constructor.java:423) [?:1.8.0_292]
28.10 22:46:50 [Server] INFO at java.lang.Class.newInstance(Class.java:442) [?:1.8.0_292]
28.10 22:46:50 [Server] INFO at net.minecraft.launchwrapper.Launch.launch(Launch.java:98) [launchwrapper-1.12.jar:?]
28.10 22:46:50 [Server] INFO at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
28.10 22:46:50 [Server] INFO at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_292]
28.10 22:46:50 [Server] INFO at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_292]
28.10 22:46:50 [Server] INFO at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_292]
28.10 22:46:50 [Server] INFO at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_292]
28.10 22:46:50 [Server] INFO at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:70) [custom.jar:?]
28.10 22:46:50 [Server] INFO at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:34) [custom.jar:?]
28.10 22:46:50 [Server] main/INFO [mixin]: SpongePowered MIXIN Subsystem Version=0.7.11 Source=file:/./mods/malisiscore-1.12.2-6.5.1.jar Service=LaunchWrapper Env=SERVER
28.10 22:46:50 [Server] main/WARN [FML]: The coremod net.malisis.core.asm.MalisisCorePlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft
28.10 22:46:50 [Server] main/WARN [FML]: The coremod MalisisCorePlugin (net.malisis.core.asm.MalisisCorePlugin) is not signed!
28.10 22:46:50 [Server] main/INFO [mixin]: Compatibility level set to JAVA_8
28.10 22:46:50 [Server] main/WARN [FML]: The coremod SpongeCoremod (org.spongepowered.mod.SpongeCoremod) is not signed!
28.10 22:46:50 [Multicraft] Server shut down (starting)
28.10 22:46:50 [Multicraft] Not restarting crashed server.
28.10 22:46:50 [Multicraft] Looks like a crash, check the server console. Return value: 255
28.10 22:46:50 [Multicraft] Server stopped

someone help me pls

The error you have there is completely different.

It clearly states that there is a missing file within your world folder (session.lock). This file is responsible for preventing the world loading twice.

If you have a backup of the world you can typically grab it from there. Im not a expert in world file structure, so someone else maybe able to help you. That being said, to get attention of others I would create a new forum post rather then replying to a forum post that has nothing to do with your issue.

Edit:
I didnt see that you had already created the second post