Fail to decode packet clientbound/minecraft:update_advancements

[Z3r0xh]

Describe the bug
I think this problem persists in packetEvents, since removing packetEvents does not give this error

Software brand
NullcordX 3.8.8
lobby pandaSpigot last build
backends UniverseSpigot 1.21

Plugins
Proxy:

Lobby:

Survival:

How To Reproduce
Steps to reproduce the behavior:
Just entering through the proxy and this error appears,

Sometimes it lets it play for a while but it ends up appearing

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

Additional context
Buil #536