Steps to Reproduce the Crash

I'm playing on All the Mods 9 (with a couple mods added) and i've tried to make a server with said dedicated server file etc...
Step 1: Make a minecraft server with forge-1.20.1-47.3.11
Step 2: Join server
Step 3: Opening inventory crashes the game immediately back to launcher

(first time issuing something on github don't be mad pls)
My friend also tried joining and same thing happened.
I get this error in the crash log, no clue what it means : "java.lang.IllegalStateException: item has no key in the Item registry: 1 air net.minecraft.world.item.Item"
crash-2024-12-22_01.19.09-client.txt

Mod Pack URL (Optional)

https://www.curseforge.com/minecraft/modpacks/all-the-mods-9

Mod Pack Version (Optional)

0.3.5

Extra Notes (Optional)

No response

Crash Report

https://gist.github.com/AkinoNya/9bbb2bc8fe2007d41ec4618702120fb9