[BUG] 1.16.5 Internal server error

[IsNevis]

For skin fetching problems

• I have tried generating skin manually on mineskin.org and it works there.

Issue

• I'm not using TLauncher (it messes up the skins, also, piracy is not supported)

Describe the bug

Server loads with the mod for first time them from next time throws error

To Reproduce

Steps to reproduce the behavior:

1. Join server with mod
2. join sucessfully
3. leave server
4. try to join server
5. get kicked with an error: Internal server error

Logs

https://pastebin.com/ixaMMx1J

Are you using any other mods?

server mods : https://i.imgur.com/L4wrA20.png

Additional context

• Tried on vanilla client too and still kicked
  Server Version : 1.16.5
  Java Version : tried on both 8 and 17

[IsNevis]

sigh.. i somehow ignored the issue with my problem.... for anyone in the future the problem is because of "tic-tacs" mod