Issue Description
One of the players was in the Nether. He had to log out of the server but when he tried to log in again a few minutes later, the server crashed. It happened the second time to the same player and only him.

Modpack version (Do not use "latest")

1.49

Logs

1. https://hastebin.com/dekonuqobi.rb
2. https://hastebin.com/usukadujaq.rb
3. https://hastebin.com/etehujacef.rb

Screenshots

NONE

Additional context

Additional mods:
-LagGoggles 1.12.2-4.1
-NetherPortalFix 1.12.1-5.3.17
-Login Shield 1.12.2-3-g7c6e7ac

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I deleted only this player's files (/world/playerdata/) from the server and then uploaded other from the previous backup. It worked for ~24h

This is only happening for one player. The remaining players log in to the server normaly .
After entering the nether by another person who uses the same portal everything works

"/cofh killall" did't help

Hm, strange issue. There's a config in the Forge config to remove retiring entities, set that to true, and please let me know if the issue gets fixed :)