Verbally abused

Today (28 Dec 2018) I went to Mr Price in Adderly Str. to return an item. I was standing in the Q waiting my turn. In front of me was 3 girls chatting away...no problem with that. When the cashier called next a few times I just politely told them "next please" and straight away I got attitude from them. When the next cashier called again one girl still feel the need to carry on to give me attitude so I told her that I'm going if you not interested. So when I got to the cashier this girl came screaming and saying it's her turn. Now...I would have expected the cashier to say to this girl that I did call a few times and you ignored it. But in stead she ignored me and helped the other girl which I then completely lost it. The 3 girls preceded to carry on in the shop with me shouting at me and verbally abused me. No manager or supervisor or cashier took charge by telling them to calm down in the shop. I couldn't believe that this was happening to me in a nationwide chain shop. It's absolutely disgusting!!