music stops playing after a few minutes

[anitagray]

I have the free Spotify app on my iPhone.  It worked just fine to play at work until about a week ago.  Now it will play songs only for a few minutes and then just stop on one of those ads and won't play again.  I have to either shut my phone off and turn it back on to reset the app or delete the app and load it again in order to play more music.  Does anyone know how to fix this?  Thanks in advance for the help