worst service ever

I have been a life long client of MTN. MTN contacted me a while ago to inform me that I can upgrade. This is where everything started to go wrong. I went to two different MTN franchise outlets at two different Malls in George and unfortunately they could not supply me with the phone that I was looking for. I then decided to ask MTN to courier a phone to my home address, as MTN confirmed that it could supply me with the paticular phone within three working days. The phone was not delivered on time and I cancelled the delivery. During this process, MTN has already upgraded me, without me signing any papers and whats more, they upgraded me onto my old phone, not the phone that was supposed to be couriered to me. This entails that I have in fact not been upgraded at all. The crux is that I cannot upgrade until MTN has corrected their system. Ihave sent numerous E-mails to have the situation corrected and made hunderds of calls to every MTN Department that you can think of but to no avail. MTN does not get back to me at all to inform me of the progress to correct their system. The phone that was sent by courier has already been returned to MTN. This is the worst service I have ever experienced from any company.