DON'T USE MTN

I got a Galaxy s6 Edge plus on contract over a month ago. I could not receive calls so I returned it to the shop. They replaced it with another unit. The same thing happened. I have since shut that contract and two others down. The coverage dept contacted me and requested to pick up a booster that was installed 3 years ago that never worked as installation was faulty. I said to the gentleman that called that I still had a few contracts but the booster was removed. I said that many in the Farrarmere area had the same issues. I requested that a booster be installed to blanket the area and he agreed to deal with it. Never heard from him again. I was contacted by MTN and there was an apology and a request to give it another chance. I went and upgraded. Received the Galaxy Note 5. The exact thing has happened. I cannot receive calls when the phone is set on LTE. The LTE handsets usually drop down from LTE to 3g in order to receive calls but this does not. I contacted the store and was told that all the handsets were using category 6 LTE and MTN was not yet ready for LTE 6. How does MTN sell handsets that they cannot use on their network? I will certainly be returning the handset today.