phone repair

im an angry customer who have been with mtn for too long,the service was right until I had to buy contract phones(2) 9720 blackberry in 17 February 2014 at jabulani mall .in april it got broken and had to send it back to the shop for repairs which happened but 6 months later the very same problem happen in November the very same year,running back to march if im not mistaking and was replaced with a\refurbished phone". what makes me angry is that the problem is with the usb chargering socket that keeps being damaged. so now recently in july send it back again and charged 1680 for fixing that"