Troubles on my Samsung Galaxy 3

[gemmayost]

I signed out this a.m. and now my App doesn't work to get me back in.  I tried signing back in another way and my playlists still dont appear.  I went to the troubleshooting guide, but if I erase the App as suggested, I will lose all my data.  I put a lot of work into my playlists.  I'm frustrated.

[licenced]

So what happens? Are you sure you're not getting a space character inserted at the end of your user name when you try to log in? Some android keyboards will add one automatically so double check