Cosmo City McDonald's staff don't have a good service

Didn't get a good service from Zanele the manager and Kgontse Mahlangu at MCDONALD'S Cosmo City, I asked for Big Mac regular meal, they said they only have medium and large,so I asked many times and they were annoyed ,due to the queue behind me she ended up placing a Regular meal for me,so I don't know why should someone can lie ,I was so annoyed that she didn't value me as a client,mind you I'm a regular customer there Angie