So my dedicated server is crashing and I have no clue what mod it is, I tried loading a non-dedicated server and it refuses to load so the mod checker won't even help.

ERROR: General , 1697359952707> 17,081,005,709> GameServer.main> Exception thrown java.lang.NullPointerException: Cannot read field "delegate" because "<local0>" is null at ItemPickerJava.Parse line:123. Message: Exception Thrown
ERROR: General , 1697359952707> 17,081,005,709> DebugLogStream.printException> Stack trace:
java.lang.NullPointerException: Cannot read field "delegate" because "<local0>" is null
at zombie.inventory.ItemPickerJava.Parse(ItemPickerJava.java:123)
at zombie.iso.IsoWorld.init(IsoWorld.java:2313)
at zombie.network.GameServer.main(GameServer.java:702)
LOG : General , 1697359952707> 17,081,005,710> Server Terminated.

This is the error I keep getting everytime I try to start up the server