Bad service

I got a Sony Z3 compact on contract with mtn. Within a week the screen just cracked. They refuse to fix the phone. According to them it is due to vandalism. Got the phone back unrepaired. But had to pay R33O. Because I did not accept the quotation. It was returned to me without a sim tray. I fixed the phone on my own expense. But up to now I can not use the the phone, as there are no sim tray. This is now six months that mtn is making one pathetic excuse after the other about the sim tray. So really stay away fro mtn. Even after getting hold of there head office and Sony direct. No luck what so ever. Was given another excuse and story again today by mtn