me and my friends have a server and when ever we go through the portal it just crashes the server. i got in contact with the server providers and there saying its something to do with the mod not the server. so any ideas ?

What version are you using? And please send a log. See https://git.io/mclogs

Duplicate of #96, fixed in 1.18.2

https://paste.ee/p/z71tG here are the logs and im on version 1.18.1