VW Passat GTE Hybrid 2021 Braking issue

[mickw64]

We are looking for help for a continuing issue with our VW Passat GTE Hybrid 1.4 2021 reg. Since we have owned it, just 12 months, it has had a recurring issue with the Braking and has been into the dealership a few times to get it checked and every time it has been 'we cant find anything wrong'.I have several very close encounters with pedestrians and being unable to stop at low speed when the vehicle continues to drive/drag forward.  Since May the vehicle has had the AA VW Assist out to check this braking problem and they found an intermittent fault with the braking system. The AA also diagnosed an issue with the Differential grinding. So it was taken into the VW dealership we purchased it from with dash cam footage and a Warranty Claim for a new Differential and Gearbox, as they are a complete unit, a New Braking Boost Unit was replaced at a cost of £11,220!  So we had a hire car for 6 weeks whilst this process was carried out. We were shocked that VW HQ actually approved this Warranty Claim to be honest it would have been cheaper to change the vehicle. So yesterday after having the car back for some 10 days, we were out driving and low and behold the brakes did exactly the same thing again and we were unable to stop the car sliding yet again. Has anyone else had this issue as it is becoming so dangerous now and we feel we have had enough of this continuing anxiety and have lost faith in the vehicle now. What would you do in these circumstances?