Look at only your throwing arm during your delivery. A couple of things that seem apparent on video are a lack of forearm layback or limited external rotation. Your arm seems to come forward maintaining an L shape. Your elbow needs to come forward before your pitching hand. This is something I work on using a weighted ball--even a 12 oz ball works good for this. (Don't throw it, of course) I hold the ball up in the high cocked position and rotate my shoulders leaving the ball stationary for as long as I can, then I rotate back to high cocked and repeat several times.
The elbow will come around with the shoulder and the ball will stay behind. The forearm will layback and you will feel your external rotation. I work on that feeling and it adds whip to my forearm.
You also seem to get to cocked position very late. You are rotating forward and the ball has not gotten above your shoulder height yet.