I almost can’t believe that after about 3 hours of trial and error - it is working now.
The solution was not not not (as it says in the instructions) to press the home and spot clean button until you hear the beep!
All you have to do is briefly press the home button and it works like a charm.
I am probably an idiot and everybody knew about this, but I will still leave this post here - maybe it will save somebody some time, blood, sweat and tears 