Uber has slipped and it's getting worse...

If I could rate no stars I would. I pre-booked an Uber X ride (approximately 2 and a half hours prior), and the driver accepted (Ar*******). He the arrives in a Mercedes Benz C-Class which is clearly not an an Uber X and then proceeds to tell me, once the passenger had gotten in to the car, that he accepted the ride in error. After much "to and fro" he says that he'll cancel the ride but I have still been charged and no refund has been forthcoming. I don't think he cancelled the trip and has kept the R160-00. Why didn't he cancel at the time of the mistake? Why drive all the way here to tell me "he accepted in error". The app is also not user friendly to be able to actually communicate with someone either. Please refund me my R160-00