The player writes to the chat and as a result he is kicked, and the error is reproduced in the console.

1. Log in to the server
2. Writes to the chat (just a message, not a command).
3. Departure from the server + error in the console.

Screenshot:

ProtocolLib dump:

dump-2023-01-21_01.02.19.txt

Translation from Russian into English was made through Google Translate.

Some plugin that writes incorrect data in the packet needs an update. try updating or removing plugins like tablist plugins or npc plugins