Question:

So I play tennis competitively and I used to have a slice serve. However I stopped taking lessons because of the cost and I started playing with one of my friends who is way better than me. But now I have lost that serve but my shots are all great and my speed ws way better than before, why did this happen, is it possible to fix without a coach?

Answer:

Hey,

I am certified pro, so you may not be able to fix the issue without a coach, but at least this advice doesn't cost money. You have definitely developed a flatter serve. There is technically nothing wrong with a flat serve, but you should have the ability to hit flat and spin serves. I'm going to recommend some videos from my site. You may want to try brushing up the back of the ball after your toss. Its important that you come from underneath the ball and hit up on it. I'm also assuming you are using the continental grip? 

Thats about all I can say with the information you have provided. It would be dangerous for me (or anyone else) to give you perfect advice without seeing you hit. 

Here are some videos I THINK will help

The Topspin Serve

The Flat Serve

All 30 Serving Videos and Articles

Serve Topspin and Kick Serves Explained and Demonstrated

A Trick to Hitting a Wicked Kick Serve

Thanks,
Steve Viglione
USPTA Pro