Complaint

Goodday, I am not impressed with the service I received from one of your cashiers, this is the Engen garage at Cresta. The lady's name is Fiona, and we had an altercation. I regularly do visit the garage to get some necessities, buying pasta mostly, and twice I had told that they did not have cutlery (a fork), so, I asked the lady if they did have supplies before I could buy, so I know to switch to bread rather, she then proceeded to tell me that I can always eat with a s****, rudely so, I still remained calm, I told her okay, because I was running out of time and it was getting late and I was really hungry. She then got up to find me a fork, and I asked why does the garage not have enough supplies when they sell food, and she answered " since you know we haven't had them in a while, why don't you wash it and keep it with you forever", how does one do that since it's disposable? My question is, so if a customer is hungry, gets to the garage to get some food, must she be told this? I then asked for her name and that's when things took a turn, she continued to be rude and told me I won't get her information, I then took out my phone to take a video of her and told her I didn't appreciate her service, she attacked me and said I mustn't take pictures of her and my food that I had just bought was on the floor, my phone slipped and I managed to catch it, I bit her hand in my defense,she then locked the door and said I will not go out until I delete the pictures/videos, now other customers cannot come inside to buy, the petrol attendants aren't able to work as well because of this, she threatened me so many times and said she'll get me, she knows where I work, she even said she wants to beat me up but we must go outside, or at the toilet, she continued to boast at how the cameras at the store weren't working. I'm getting late now and need to return to the office, but the doors are locked, luckily loadshedding hit and the doors opened. When I went out people already knew what was happening, and not even one person defended her, they even said this is how she is, even the colleagues have me a go ahead to report this because they know her. So now what must happen to me? Must I resign at work because she threatened to get me? Must I stop buying at the garage because she might be waiting for me? What kind of service do you guys offer? Something must be done about her, people aren't happy about the service she gives. Fire Fiona or move her to a different garage. I'm more than happy to send the videos.