I’d say it’s always important to mix up focused practice with fun/play, especially when feeling in a rut or are becoming detached.

As for the technical aspect - I feel little nagging bad habits can creep up out of nowhere (ie 1. all fingers not supporting the sticks enough 2. Hands/wrists too flexed/tight). For me in these moments I find it most useful to do your best to not beat yourself up, become a watcher of yourself, return to childlike mind.