Help: hip rotation


#1

My throw side hip goes down, and drags my throw side arm down. My throw side hip is lower when I release the ball. The hip goes up after I release the ball. The throw side hip moves in “U” shape.
I watch many pitch videos, all have higher throw side hip during their releasing balls. The throw side hip moves in a “n” or “-“shape.
I pitch wild, does the lower hip rotation cause the problem? If yes, what drill can help me to correct it?