Thanks for taking the time to open a bug report!

Describe the bug
seems to be working very well. it just tells me this

To Reproduce
i updated ItemJoin. then this error appears.
i think something broke it. but consider that this happens after the update. so im created issue for this

Expected behavior
this is just spam. i have no problem in practical application.

Screenshots

Pastebin
it is only sent to operator. the console does not found any itemjoin error(s)

Please complete the following information:

• ItemJoin v5.2.5-RELEASE-b850
• Purpur-1171 MC1.16.5

Additional context
i dont think i can offer more effective things. if need u can tell me what u need me to provide.