Staff lady polite to everyone except the black customer

I had the a terrible experience with a ****** "waiter" at this Cheltenham KFC. She was polite abd professional with everyone else but me. I ordered a 3-piece variety and she was very impatient asking me which one, eveything else that I ordered after that was just hope that I was going to get the right thing. Then my order was nowhere to be found, when they asked her she said it's because I did not know what I wanted(said that right infront of me), I was now sat with a receipt but no food. I eventually asked to speak to her, she took her time and when she arrived I asked her to call her manager. As I was explaining to her manager what haf transpired, she tried to speak over me. I did not allow her then she walked away screaming "oh my god!" right infront of her manager. Is that the caliber of employees KFC Cheltenham is grooming! The other staff was amazing in finding my order and big ups to them, we really appreciate their service as customers.