Ryu, Fei Long and Dudley. Why don't my crossups, crossup?

More often than not when I attempt a crossup I end up overshooting my opponent without hitting them and I either: get thrown, or eat a big combo. I use mk for crossups as Ryu and Fei Long. I have no idea for Dudley.

What should I do to improve?

dudley doesn’t have a cross-up. figure out the proper spacing for your cross-ups with ryu and fei and practice it over and over.

Practice. It’s a simple j.mk with ryu.

With Ryu’s j.mk I usually try and land the back part of the kick on the enemies head. This prevents me from getting dp’d on wakeup and it works as a crossup.

Feis cross up MK has to be quite close to the opponent in order to cross up.

This question is way too vague to give you any insight that might work. But if it didn’t hit then you either messed up the jumpin spacing, or they moved. There are plenty of normal moves in the game that will change their hit box, making them harder to hit, or they walked/crouched under you. Video example would help of how this is commonly happening to you.

Dudleys cross up is thunderbolt. Good luck with that!