MTN - 5 weeks and no service

I have asked for a number change on my MTN contract i the 2nd week of September 2018 at the MTN store at Centurion Mall. They told me i had to pay, gave me a new sim. and said it will take 7 days. In the next 5 weeks i have been to the store 5 times, and they still can't sort out my problem. It have been very uncomfortable being without a phone, and i have paid for services i havent received.