I think I am using the latest version of every mod I have. I am using MultiMC with Fabric and no matter what I do I cannot fix it. I am also terrible at reading logs so... yeah.

https://pastebin.com/DR3ejHip

Suppressed: java.lang.NoClassDefFoundError: net/minecraft/class_1789
    at net.simplegrinder.SimpleGrinderMod.onInitialize(SimpleGrinderMod.java:18)

Simple Grinder needs updating to the version you are running on before it will work.

Ok so... I deleted Simple Grinder and it works now...

Can be closed?