Useless and *********** Midrand repair centre.

My Nokia 930 phone became faulty 2 weeks after I got it at the MTN store in Cresta shopping centre. Whenever I made or received a call the screen would go black and I would be unable to terminate a call. I would also be unable to use the voice message service as I could not perform the voice commands requesting me to press the options numbers requested as I had a black unresponsive screen. The phone has been to the Midrand Repair Centre 5 times now. It has had nearly all internal parts replaced and software reinstalled several times and every time I get it back \repaired"the black screen problem remains and I continue with a phone that I cannot use. Their so called \""technicians\"" do not even bother to test the phone after repair to see if the problem is fixed before sending it back as repaired. This has now been going on for 9 months and I am paying off a phone that sits in a drawer because I cannot use it and have to use a lower model Nokia 630 that I got around the same time and is working perfectly. If they couldn't fix it they should have replaced it not just hand it back nonworking and hoping that I would give up. This is not service for a customer of 20 years contract."""