phone repair

I upgraded my contract earlier this year and I got new phone,within 7 days it stopped working and was taken to repair.A week later it came back and same problem occour. I took it back against took another 14-21 working days and I don't have a problem with that.<br> I went to fetch it last week 13th Feb and 5 days later its not working again.<br> <br> I need a new phone because its obvious the one I have it has factory fault. I was told the shop cant give me a phone head office must aothorise that.<br> <br> In the mean time I am paying my subscription..I am not happy with cell c at all.<br> <br> Do I have to put a banner to be assisted.<br>