All songs went missing

I recently got the Sansa Clip about 2 days ago. I loaded songs and everything was working fine. Today, I paused during a song and set it down for a few minutes, it auto-powered down (like it always does to save energy). When I came back to resume the song. All of my songs were gone, even the songs that came with the device. Now it says that I have 1.53 GB of used space and only 350 MB of free space. What is the issue?

Something similar happened to me and I was able to retrieve everything thanks to advice from this forum.  Check out the thread below from me listed as reformatting the clip.   I did not have to reformat and reload everything.  Good luck.  I hope it works for you! 

You probably pressed the format option in settings