what is the problem with my sunroof if start to open and suddenly stops, then you need time to close it back?
At the time to close it, it moves just a little and you need to leave it alone, few minutes then try to close it again.
It sounds like it might be the electric relay. Perhaps the sunroof moter has a little drag, either from missalignment of just age, the extra load on the motor can cause the relay to get hotcausing it to over heat, and need to cool off then it works again. You can check the electrical load with an amp meter.