The female seems a little young, but she could be in heat. He will still try to mate with her, even if he is neutered. Maybe you should try and sit up and watch to see what they are doing. If they are just playing tag, then it's probably fine. If they are doing a lot of hissing or balling up and crabbing at each other, then they may be fighting.
Also, if you haven't had them together long, they may still be trying to figure out who is in charge. Check to make sure neither has any sort of wound or infection that the other is over grooming.
Do you have more than 1 cage of gliders? Maybe you need to separate the cages a bit more.