I am starting this thread to handle any VW cars with P0455 repairs that also have the symptom of an inability to fill up without restarting the gas pump lever. The motivation behind the thread is that we can split the P0455 problems down into two cases: one where there's this filling up problem and one in which there isn't.
Most threads regarding P0455, like checking the gas cap seal, obviously are irrelevant for my case (when the gas cap is supposed to be off the gas pumping ?overpressure sensing? valve disengages the pump open valve handle). I think based on hours of reading that the most common solution for the non-fill up problem case of P0455's is the N80 valve/solenoid. But I know that's not the problem if you also have a fill-up issue.
Anyway, given that I have a fill up issue and a P0455, what's the best ideas on how to fix? I looked at ross-tech and is rather worthless. (None of the solutions is relevant or I already replaced that part and it had no effect.)