Cashier Insulted Me and Shouted Me like I'm a 5 year old

I went to PEP Mayfield square to buy some stationery for my daughter (5 A5 exercise books 48 pages), but the service I got from a cashier name SIYANDA was SUPER HORRIBLE. I was insulted, shouted at like I'm a 5 year old little boy, intimidated and told on my face that I will not be assisted of which she kept her word and not assisted me. I told her Manager Refilwe and her manager told her to apologize and she didn't want to apologize even other customers asked her to apologize but she didn't want to instead she gave me an attitude and said "sorry ke" after being asked more than 5 times by her manager.

I've never felt like this nor treated like this in my whole life as a customer and this behavior is totally unacceptable and I want some action taken for this girl because she doesn't deserve to be in the store if she treats customers with so much disrespect. So please attend to this matter urgently because what I experienced is still going to carry on to other customers who maybe won't be nicer like me and not beat her up.