Why aren’t my AirPods case charging?

Hi! I have the first generation AirPods, and I’ve used them almost daily since September. Unfortunately, the case seems to have stopped charging. The AirPods themselves are charging when the case is plugged in and working. The indicator in the case turns orange, but on the phone the show up dead and not plugged in. Is there anyway to fix? Or is it a phone thing where it says it’s not charged but it is?