Pixelmon 1.12.2 Server Crash

I am a staff member from the server I-Pixelmon and we have this issue where if someone has too much of ore any ore it will crash the server. We don’t know what’s wrong and going on if someone can reply and contact me back that would be helpful. The Grief Prevention is basically not working.

-ItzSceptic I-Network Staff Team

Heres a more detailed description:I was watching a player, he was xraying at first. He sold diamonds to buy lapis. He then made a crafting table and began doing something inside it, then the server was badly lagging and I mean badly lagging. From what I saw lapis was turning into coal , he never bought coal. Soon after the server crashed. He then tried it again and the server crashed again. 5 mins later a new account joins, goes to a warp, then back to our blacksmith shop and buys coal and lapis.

A crash log and mod/plugin list would be useful