Very unprofessional, should not be working there

My partner and I went to MTN to get a SIM card for his Xperia Z2. When they had given him a SIM card, he had asked for someone to help him place the screen protector on his phone, but none of the employees working there sounded as though they were capable of doing so (which is unacceptable if they are working in the cell phone industry). Vodacom was more than able to do this for my phone and did it in around 2 minutes. Eventually after waiting for a while a man did it for him. They were unable to do a sim swap for him as the systems were off, so we went back the following day, only to see that instead of a Micro sim for the Z2, they had given him the Nano sim for the Sony Z3. I find this very bad service and it doesn't seem like they know what they are doing. I had also asked a lady to keep a cover for me for a few days and she rep**** with a ****y response saying, 'first come first serve'. I myself am in the retail business and we are almost always able to keep something aside for a customer, even if it's only a short period of time. I will not ever recommend MTN to anyone that I know.