TP power on not working

Hi,

I have the problem, that the power on button on teach pendant is not working for our 10e. We tried using the TP on another UR10e and it worked. So the problem should be in the control box.
The 24V and TP 48V leds are green if we push the button. (Only these two LEDs are green)
But the TP is not starting.

Help is urgent
Thank you