Pixelmon Server Crash!

My Server have like 10-15 member only at same time . and usually crash by this problem . can someone help me fix this
---- Minecraft Crash Report ----

WARNING: coremods are present:
SpongeCoremod (spongeforge-1.12.2-2838-7.3.0.jar)
Contact their authors BEFORE contacting forge

// I feel sad now :frowning:

Time: 11/7/21 11:41 AM
Description: Exception in server tick loop

java.lang.NullPointerException: Exception in server tick loop
at net.minecraft.server.MinecraftServer.handler$zof000$mapOptimization$onEndTickMapOptimization(MinecraftServer.java:5303)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:713)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
at java.lang.Thread.run(Unknown Source)

A detailed walkthrough of the error, its code path and all known details is as follows:

– Head –
Thread: Server thread
Stacktrace:
at net.minecraft.server.MinecraftServer.handler$zjg000$onCrashReport(MinecraftServer.java:4687)

– Sponge PhaseTracker –
Details:
Phase Stack: [Empty stack]
Stacktrace:
at net.minecraft.server.MinecraftServer.handler$zjg000$onCrashReport(MinecraftServer.java:4687)
at net.minecraft.server.MinecraftServer.func_71230_b(MinecraftServer.java:889)
at net.minecraft.server.dedicated.DedicatedServer.func_71230_b(DedicatedServer.java:371)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:558)
at java.lang.Thread.run(Unknown Source)

– System Details –
Details:
Minecraft Version: 1.12.2
Operating System: Windows Server 2016 (amd64) version 10.0
Java Version: 1.8.0_311, Oracle Corporation
Java VM Version: Java HotSpot™ 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 5558301464 bytes (5300 MB) / 10737418240 bytes (10240 MB) up to 10737418240 bytes (10240 MB)
JVM Flags: 20 total; -Xms10G -Xmx10G -XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200 -XX:+UnlockExperimentalVMOptions -XX:+DisableExplicitGC -XX:+AlwaysPreTouch -XX:G1NewSizePercent=30 -XX:G1MaxNewSizePercent=40 -XX:G1HeapRegionSize=8M -XX:G1ReservePercent=20 -XX:G1HeapWastePercent=5 -XX:G1MixedGCCountTarget=4 -XX:InitiatingHeapOccupancyPercent=15 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:SurvivorRatio=32 -XX:+PerfDisableSharedMem -XX:MaxTenuringThreshold=1
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
FML: MCP 9.42 Powered by Forge 14.23.5.2854 29 mods loaded, 29 mods active
States: ‘U’ = Unloaded ‘L’ = Loaded ‘C’ = Constructed ‘H’ = Pre-initialized ‘I’ = Initialized ‘J’ = Post-initialized ‘A’ = Available ‘D’ = Disabled ‘E’ = Errored

Mods:

| State  | ID              | Version           | Source                                     | Signature                                |
|:------ |:--------------- |:----------------- |:------------------------------------------ |:---------------------------------------- |
| LCHIJA | minecraft       | 1.12.2            | minecraft.jar                              | None                                     |
| LCHIJA | mcp             | 9.42              | minecraft.jar                              | None                                     |
| LCHIJA | FML             | 8.0.99.99         | forge.jar                                  | e3c3d50c7c986df74c645c0ac54639741c90a557 |
| LCHIJA | forge           | 14.23.5.2854      | forge.jar                                  | e3c3d50c7c986df74c645c0ac54639741c90a557 |
| LCHIJA | spongeapi       | 7.3-7127e0882     | spongeforge-1.12.2-2838-7.3.0.jar          | None                                     |
| LCHIJA | sponge          | 1.12.2-7.3.0      | spongeforge-1.12.2-2838-7.3.0.jar          | None                                     |
| LCHIJA | spongeforge     | 1.12.2-2838-7.3.0 | spongeforge-1.12.2-2838-7.3.0.jar          | None                                     |
| LCHIJA | pixelmon        | 8.3.1             | Pixelmon-1.12.2-8.3.1c-universal.jar       | None                                     |
| LCHIJA | pixelextras     | 2.5.14            | PixelExtras-1.12.2-2.5.14-universal.jar    | None                                     |
| LCHIJA | trainercommands | 2.5.1             | TrainerCommands-1.12.2-2.5.1-universal.jar | None                                     |


Plugins:

| State  | ID                    | Version               | Source                                         | Signature |
|:------ |:--------------------- |:--------------------- |:---------------------------------------------- |:--------- |
| LCHIJA | clearmob              | 1.12.2-3.0.1          | ClearMob-1.12.2-3.0.1.jar                      | None      |
| LCHIJA | pixelmoneconomybridge | 2.0.8                 | EconomyBridge-2.0.8.jar                        | None      |
| LCHIJA | economylite           | 2.15.1                | EconomyLite-7.1.0-2.15.1.jar                   | None      |
| LCHIJA | flexiblelogin         | 0.17.4                | flexiblelogin-0.17.4.jar                       | None      |
| LCHIJA | impactor              | 3.1.2                 | Impactor-Sponge-7.1.5-3.1.2.jar                | None      |
| LCHIJA | localeapi             | 1.0                   | LocaleAPI-1.0.0-S7.1-RELEASE.jar               | None      |
| LCHIJA | violet                | 2.4.2-SNAPSHOT        | SpongeViolet-2.4.2-SNAPSHOT-shadow.jar         | None      |
| LCHIJA | locket                | 1.2.0                 | Locket-1.2.0.jar                               | None      |
| LCHIJA | luckperms             | 5.3.71                | LuckPerms-Sponge-5.3.71.jar                    | None      |
| LCHIJA | mmcrestrict           | 1.5.1                 | MMCRestrict-1.5.1-API-7.jar                    | None      |
| LCHIJA | nations               | 2.11-S7.0-MC1.12.1    | Nations-2.11-S7.0-MC1.12.1.jar                 | None      |
| LCHIJA | nucleus               | 2.4.0                 | Nucleus-2.4.0-MC1.12.2-SpongeAPI7.3-plugin.jar | None      |
| LCHIJA | chatpixel             | 1.80                  | PixelChat-1.80.jar                             | None      |
| LCHIJA | pixelgenocide         | 1.1.1                 | PixelGenocide-1.1.1.jar                        | None      |
| LCHIJA | placeholderapi        | 4.4                   | PlaceholderAPI-4.4.jar                         | None      |
| LCHIJA | protocolcontrol       | 0.0.2                 | protocolcontrol-0.0.2.jar                      | None      |
| LCHIJA | skitskurrsranchloot   | 1.0                   | RanchLoot.jar                                  | None      |
| LCHIJA | safetrade             | 1.12.2-3.2.2-PIXELMON | SafeTrade-1.12.2-3.2.2-PIXELMON.jar            | None      |
| LCHIJA | virtualchest          | 0.4.6                 | VirtualChest-0.4.6.jar                         | None      |

Loaded coremods (and transformers): 

SpongeCoremod (spongeforge-1.12.2-2838-7.3.0.jar)
org.spongepowered.common.launch.transformer.SpongeSuperclassTransformer
Profiler Position: N/A (disabled)
Player Count: 0 / 40; []
Is Modded: Definitely; Server brand changed to ‘fml,forge,sponge’
Type: Dedicated Server (map_server.txt)