Appalling service at MacDonald's Ghandi sqaure

On the 13th of March 2020 at around 10:22 I went to MacDonald's at Ghandi square(JHB) and ordered chicken club sandwich and asked that they add an egg as an extra in the sandwich. When my order arrived the egg was not included in the sandwich but was put separately in another box. The name of the lady who was serving me is Disebo, I asked her to take back the sandwich and egg and to put the egg in the sandwich. She refused and said I must take it to the lady at McCafe because she is the one that made the sandwich. So I took my sandwich and left. Then I changed my mind and went back to Disebo, I found her gossiping about me to her colleagues, telling them that she doesn't know what my problem is because I could just add the egg to my sandwich when I got to my office. She could did not see that I had returned because her back was to the counter. I answered her and told her that I couldn't put the egg in the sandwich because I had paid for the service. She and her colleagues then started laughing at us(I was with a colleague). At no point did she apologise, her supervisor then came to me and took the sandwich and the egg and then added the egg to the sandwich. MacDonald's Ghandi square might receive prizes for the high sales but their customer service is appalling and it has always been that way. The reason people keep going back to the MacDonald's at Ghandi square is because it is the closest one to our office. On a number of occasions I have purchased meals that come with fries, only to find out when I get to the office that the fries are not included in my meal. A number of my colleagues have had the same experience. Please train your staff on customer service.