Error with usage rights?

[Ekelctic]

I've had my zune for a while, and have been buying from the marketplace regularly, however lately I keep getting a 'usage rights' error on songs and music vids that I had just paid for, and the 'web help' doesn't have specific help and just says make sure you're online. Does anyone know why this is error is happening, or at least what I can do to fix it?

Please and thank you!