Ragna is actually incapable of punishing an air tech unless it's neutral, and even then only with 6A, Blade.
Kayeff, you can mash as hard as you want as long as you stop when you tech.
Metaknight, that's just not true at all.
At the original post, just mash harder. But do watch out for an opponent baiting your tech, like Bang air tech traps or Tager tech traps.