Hey guys, I'm asking for help because I am absolutely stuck here.

For some reason the item refuses to show up in the creative inventory and in my custom inventory tab.
I am currently attempting to update the mod to version 1.12.2.
I know the item is registered and working because I can spawn it in with /give Player atimemod2:crystal_gem



The Github link is https://github.com/BurntRouter/ATimeMod2

Any help is appreciated thanks!