I have a hampton bay ceiling fan and both the ceiling fan and light work when the light switch is used but the remote will only work on the fan and won't turn the light off when I just want the fan to run. Any suggestions?

Does the fan have pullchains? If it's an added remote it might not be wired to the light. Otherwise the receiver might be shorted. Does the remot LED light up when you push the light button?

No it doesn't have a pull chain. Yes the remote LCD lights up. It worked well for years and then all of a sudden it stopped.

It is most likely a bad receiver. It could be a bad remote but usually it is the receiver that breaks. You can contact Hampton Bay for replacement parts or just exchange the fan at Home Depot.