I had this happen to me to. If you are plugging it into a computer, just eject the drive and it should charge. If it's a wall charger, I have no suggestion.

I had the same thing happen to me about a month ago. I tried everything, new charger, different outlets, different charging methods (computer vs wall) with no luck. I had to format it and then it would charge... lost all my music, but at least it still works.