WARRANTY IPHONE REPLACEMENT

I have relocated from East London to Joburg and my son's iphone5 was purchased on contract at Hemmingways MTN store from Mathew Gosling. The phone was taken to Midrand Repair centre and was confirmed to be faulty. I was given a collection no.*** and told to contact Geraldine the Ops Manageress who will assist me where to collect phone as she was sorting our franchise stores. I phoned her and was always told she will come back to me. Well ...... I am now dealing with tweets, emails and calls to tell me - we still waiting for feedback says Fareda who is very polite. How hard is this that a phone can be collected from store !!! My son 22 years old has cancer and this phone which he is paying for gives him a lot of joy - I have to tell him with sadness every day that I still have no positive feedback for him!!!! Come on MTN you can surely do better than this. I have resorted to this Hello Peter as I am tearing my hair out now. I want to take out a contract mmmmmm gotta rethink this one!!! :( please do not call my son's mtn phone number!