If I had to take a guess of what the problem is...
It looks like your app only needs the user's location while the user is actually viewing the screen of your app. So, I would assume that you only need to know the users GPS location when they are actually viewing the screen of your app and that you don't need to know their GPS location if your app if not in the foreground.
So, google is rejecting your app because it appears the code you are using to detect the user's location has the ability to run in a background process so that the code can obtain the user's GPS location even if your app is no longer visible on the screen. Google doesn't like that your app is doing this.
So, you need to change the code for the GPS so that it only tries to obtain the user's location when your app is visible on the screen.