why is genius or my iTunes music library not working anymore?

I'm assuming you have Apple Music given where you've posted. Turn off Apple Music AKA iCloud Music Library, then turn off Genius, delete the file if it has been recreated, then turn Apple Music back on which will turn Genius back on again. The downside is that probably invalidates any locally stored Apple Music content, but since it isn't working now you're probably going to have to wear that.

tt2

I don't know, but with iTunes closed you can delete the iTunes Library Genius.itdb file in your iTunes folder which should force it to be rebuilt next time you start iTunes.

tt2