ISSUES NOT USING OUR TEMPLATE WILL NOT BE CONSIDERED AND WILL BE CLOSED!

Describe the bug
A witcher spider hit me, I instantly "Died". As in, my health went to zero but I can no longer die now.
/kill doesn't work, nor does going to other dimensions, swapping gamemodes, deleting my player data, or restarting the server.
Void cannot kill me, nor can I go to the beneath by hopping through the void.

Cannot interact with containers or blocks of similar sort.

To Reproduce
Steps to reproduce the behavior:
Unknown.

Expected behavior
Pls no infinite die

Screenshots

Info (please complete the following information):

• Modpack Version: 2.77.1
• Server or Singleplayer: Server
• Version the world was created on: 2.77

A temporary fix:
Delete Player.dat of infinitely dead player, delete all json files related to them, Find their Player ID and delete them from the cache and configs. Player will no longer be infinite-dead upon next login.