It's the same problem that happens to me, did you have a solution with the camera? found the problem?
It was dead and needed to be replaced. My replacement just died also, same model. This time it's the PTZ function that died. Andy says it's probably a broken belt and it can t be fixed. I replaced it with yet another of the same model (I might just be a glutton for punishment here). I also had a different model Dahua die recently. They seem to have a 2-3 year life for me. I'm about ready to switch to a different brand. I expect to get 5-7 years out of my electronics, and at that point have to replace them because of new tech, not because they died.