Trouble with dash canceling Carlotta’s heavy attack.

I’ve been working on improving my mechanics and am having the hardest time using dash cancels with Carlotta’s heavy attack. Every now and then I manage to pull it off, but it’s inconsistent at best. I’d say eight times out of ten I dash cancel the heavy attack and then she immediately starts a second heavy attack, which I can’t cancel. On paper I guess it’s not that bad, as leading heavy into heavy isn’t exactly bad; but, despite that, I’d like to actually be able to do the proper cancel. Especially when I’m leading intro into heavy then the second heavy attack is just wasting three crystals.

I’ve tried varying the length of time that I’m holding the heavy, thinking I may be holding it after the dash, and I’m positive that I’m not now. I’m playing on controller if that’s relevant. I’ve tried rebinding the dash to a few buttons and none of them stopped the issue. Any ideas what I’m doing wrong?