Can't hit properly

SownCape19

I start out the fight well, however... some time after the fight starts I get the first hit (medium dash) and right after that it just spams heavy attacks, it's costing me some fights in story mode too often to be honest. Makes my unit spending not worth it at all, I just spend on revives to get downed the same way again.

Thanks for taking your time to read this (if you do... I know y'all are busy)