very bad service

I am very ****ed with mtn and their service, its very bad and they treat their clients like they doing them a favour. U will be taken from pilour to post up and down. I did an upgrade in november till today i havent received my phone. I called mtn and they said ii must call Rtt and i call Rtt they say i must call mtn the phone is taken back to mtn. I really dont know what to do but they expect to debit my account .ref no is nr***6 and the other one is ms***2 really the service is bad even supervisors dont want to assist when u want to talk to them. Imfrustrated as a client to be taken for granted like i should beg for service. This so wrong in all levels. Please assist.