Thanks for playing.
The jump to fall mechanic has a delay of a few frames, so if you don't jump high enough it might not work. I did it this way so you could land on a background platform and immediately crouch, although I don't know how useful that'd be, so maybe I'll lower or remove the delay.
I made the attack hitbox pretty big, but I've seen other people have the same issue, so it might be something else. I'll look into it.