Pathetic service

Kfc Belgravia is truly pathetic, i ordered a zinger burger, requested white sauce no tomato, box master zinger white suace no tomato and dunk the fillet, snack pops meal, come at rhw window to pick up food, they mess it up, i literally repeat my order yet the manager herself clearly cannot understand what i asked, she got it erong 3 times, then makes us wait for fresh fillets and still there she gets it wrong, gave me the back no zibger in the bag then tells me i requested no garnish on the box yet i didnt say ni garnish, i request for my money back then she still gives me the wrong change back, im sorry but i have never had such pathetic service even from a manager, i want something done about this as this hasn't been the 1st time i had a issue like this at that kfc