Suppling clients with damaged phones

I have 3 contracts with Cell C and have been with the mobile network for many years now and for this to happen is seriously discouraging. I recently took a 3rd contract for daugther for a Birthday Gift a Blackberry 9720 of which the first week of using the phone pictures couldn't be viewed the transferring of media files via Bluetooth wasn't working nor could the phone read the memory card, now I am not certain but my concern is how can such a damaged phone be given to a customer over and over. I took the phone back of which they didn't replace all they did was sent it for repairs, 2 weeks later I collected the phone within a week again the same problem reoccurred I am honestly tired of going back and forth with Cell C. For years a have supported them ensuring they are payed on time without them having to call me back and forth I dont see why they cannot give their costumers the same courtesy but this is unacceptable.