Just an update:

I took my car to the dealer today, had both guages put on to test the pressure - one on the high pressure and one on the low. The pressure was showing between 16-19 bar.

There are no leaks and my pressure is good, and the freon level is absolutely full.

So now I am really at my wits end.

1. Duovalve works fine.
2. Full refrigerant with no leaks.
3. Compressor, drier, evaporator all working fine.

Only thing left are the flaps. And that seems exhaustive to diagnose and/or repair.

I dont know how to go forward and I dont really expect anyone to give me any golden advice - I just wonder if anyone has ever worked on the flaps and if so what am I up against? And could this problem even be the flaps? Or something else?

THANKS