Hi there, just had a look at the video clip you sent. So for to generate topspin you need to change your bat angle so you can hit more on the top of the ball and the side. Right now your bat is only able to go under the ball and slightly on the side, you need to get the bat on top of the ball so you are able to brush around the side and over the ball. Also to me it looks like you are using a normal service grip here which does make it quite hard to do these style of serves, maybe have a look back at the grip video in the course where Par explains the best grip.
Answer for How To Do The Topspin Serve With Par Gerell (not kicker serve)
