Looking real real real good until....
you start that weirdo forward swing leading with your body..
Don't lead with the body, keep all the parts together and moving forwards at the same time.
You lose power by lagging behind with your arms. You get a nice arch, but you never SNAP it straight to impart swing speed.
You have no swing speed. Your motion suggests a solid 5.0 level serve, until just after the trophy position, you THROW your waist into the court...and forget to swing the racket.
Start your racket swing earlier, timed WITH your body thrust forward, and you will have the 5.0 level serve.
Oh, and your swing is like a whimpy girls. Why are you swinging in slow motion?