I reveived a new Doser Maxi and when pressing the control buttons on the front side (1-2-3-4) none of the pumps turn.
When connected to GCC and trying to calibrate the pumps, the same problem occures.
I can hear the pump motors making a sound (as if they are energized, buzzing) but they seem to be stuck.

Being a new pump, please advise what to do.
Can I open the box to see what is wrong?