this shows up as the fatel in the log https://pastebin.com/tYi6Y5q0

it's happened in 1.14.4 pre 5 with build 1 of that version's fabric loader and fabric API 0.3.0 build 192

Fabric API is not working for 1.14.4 yet, the fix is on a separate branch and can't be pushed because of a fault with their versioning system I think it was, so you will have to play on 1.14.3 for now

Update to the 1.14.4-pre5 fabric api that has now been released as an alpha.