Shocking experience

Bad and shocking experiences. I was at McDonald's on the Monday 25th 21h16. I complain about the service and the cashier (order taker) told that I'm complaining and I'm not white even if I was white he will still tell me the same thing because white are the only people that complain. I'm disgusted and disappointed. It all boils down to training and how to engage with customers. McDonald's used to be the best in service I don't know what happened. Please enlighten me because I always go to this branch I don't want to experience this kind of service.