Mp3 isn't playing transfered music

Question

I recieved a Coby MP3 for Christmas.I used my Windows Media Player to sync music to it.I downloaded the music I tried to sync from Limewire's free music service.When my computer finished syncing ,I removed my device to test it and got no sound.I then plugged back in to my computer to try the sync again but my player states that the music is already on my device.Please help me figure this out.What did I do Wrong if anything and how do I fix it?