Strange wires in my Ritto gives me sleepless nights

Hi all,
I installes an opener at a Ritto 17230. The problem is, that in a and b i don’t have just one wire, but two in each port. Apparently these wires connect my neighbor to the system. If I remove these wires, her Ritto is dead.

When I connected my opener I treated these two wires in each port as if it was one. So I took both wires from a and put them in the Nuki-clamp. But I realize, that my Nuki does not work reliable when it comes to Ring-to-Open. Opening via app always works, but often the door bell is not recognized.

If I remove my neighbors wires, everything works fine. But of course I cannot do this :slight_smile:

What should I do? What is the right wiring when my neighbor is also connected via my ritto?