I started this minecraft server a few days ago and everything was running with zero issues until someone entered the nether. basically when someone enters the nether everything is all good for about 30 seconds and then every mob freezes and blocks don't drop when you break them ect. and then about 1 min later the server crashes and everyone gets timed out.
The modpack I'm using is https://www.curseforge.com/minecraft/modpacks/create-above-and-beyond with 1 extra modded added onto it and a dependency for that mod https://www.curseforge.com/minecraft/mc-mods/rats https://www.curseforge.com/minecraft/mc-mods/citadel
The crash report it gives is at this pastebin - https://pastebin.com/zgCaJ13V
I would really appreciate someone trying to help me I've looked around and tried many things and nothing has worked.
Feel free to ask for any more information