Poor service from MTN

I bought a contract phone in June 2018. I reported the phone that it was faulty within 7 days of receiving it and they said they will send a drive to collect it. I keep calling them and the driver never came. I keep ta calling and eventually went to rosebank mall my to get assistance. The person there said I need an invoice and I must call the call centre to get a copy. I spoke to Yanga Gcasamba on the phone who then sent an email to my queries logging the request for them to send me invoice. I still haven't received the invoice and I am stuck with the faulty phone that I had reported in June. Poor service all round from my. It's been 5 months now I am dealing with one issue. Luckily the calls are recorded and there are reference numbers so this can all be tracked.