Minecraft - Internal Exception: io.netty.handler.codec.DecoderException: java.lang.NullPointerException: Cannot invoke "net.minecraft.nbt.CompoundTag.contains(String, int)" because "nbt" is null

[LimonFRE]

Internal Exception: io.netty.handler.codec.DecoderException:
java.lang.NullPointerException: Cannot invoke "net.minecraft.nbt.CompoundTag.contains(String, int)" because "nbt" is null

This problem has been haunting me since version 1.20.1 of Forge. The error appears when my friends and I enter each other's world. (But it happens that everything works without errors, for this we restart the launcher and log on to the server)
Below I will attach a list of mods.

[hlysine]

I don't see power loader in your mod list. Which version of power loader are you using? Can you update to the latest version and retry?

[LimonFRE]

[LimonFRE]

Everything worked, it was necessary to create a new world. Thank you very much! (of course, I didn't expect you to be the one to help me)

[LimonFRE]

No. This error appears again.

[hlysine]

Do you have a log for this error? How exactly did you see this error text?