1999 Integra

The obvious is that if it works and then doesn't work you could have an overworked motor. In other words, it could be the motor or a relay but you might want to look a little bit deeper into what is causing the problem which could be that the tracking is dirty, needs lube, etc. You can close the sunroof by hand. There is a section in the book about doing it and honda/acura usually provide a tool in the trunk to allow you to close by hand.