Rude and Unproffessional

I went to Jam in Mams mall on the 09th Feb on a Tuesday after gym, that's where I buy my gym clothing. I was nicely greeted by a gentle ma. At the door who's name is Patrick who I had discovered later that his the store manager. I went to pay my items at the till point the cashier didn't greet but I ignored that, she asked me cash or card I said cash then I told her I want to change the item I had for a cleaner one. On my return she scanned everything then when I took out my bank card she immediately asked me so rudely with an angry face did I not say that I'm buying cash. I rep**** "yes" but I remembered I'm going to need the cash for later she got so upset and I asked why is she so angry and giving me attitude. She went on and on of how she now has to change systems to use card that's why she asked. Now i got very angry as how rudely she spoke to me as if I'm a child and had no respect for customers, the gentleman I had met early at the door came rushing to rescue. He immediately told the cashier Inni Msiza to keep quiet but she did after several times she kept quiet. I had told her and the manager that there are so many people who desperately need jobs and could do a better job then the rotten potato he hired, she never showed remorse nor apologized. I'm really disgusted at how customer service doesn't exist to most employees, she needs to be disciplined, offered customer service training and professinalism. She doesn't belong in retail. The Manager need to intervene in hiring staff and remove rotten potatoes like Inno Msiza