Check log here!
https://pastebin.pl/view/adeee54c

Try to use dev build of ProtocolLib v5.1.1 from here:
[1.8-1.19.4]: https://ci.dmulloy2.net/job/
[1.20.*+]: https://ci.dmulloy2.net/job/ProtocolLib/669/

Notice for 1.20 and 1.20.1 users:
Please, use 1.20.2 to confirm your issue with ProtocolLib.

Why not the last build for 1.20.2?
Last build (673) have critical issue at this moment; #2601

If the problem persists, provide more information about your problem using this form:

• This issue is not solved in a development build

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Version Info
Provide your ProtocolLib install info with /protocol dump through pastebin.

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