Disgusting service ever

On the 17th I visited garlitos in Mabopane block x next to pick n pay and Sasol garage. I placed an order and later noticed that there was a mistake with my order which I didn't think was gonna be an issue. I went to the counter to fix my order and I spoke to letlhogonolo Matlhabe who called the lady who was assisting me. Before I could finish what I wanted to say the lady started screaming at me saying next time I should speak louder. She totally went crazy on me and I was shocked for such a behaviour especially at such a reputable establishment and in front of other customers. I asked for the manager and I was told that she's not in. I asked for the lady's name since she wasn't wearing a name tag and she just said her name is Tabu, when I asked her colleagues for her last name they told me that they don't know it. I felt really dissrepected by the staff's behaviour towards me. I will never set foot in that store again. I've visited many garlitos before and the treatment was really professional.