MTN upgrade - good luck!

I have being trying to upgrade my MTN prepaid contract since April when it expired after two years on a roughly R780 per month contract but there has been a bug on my account that I was initially told was an easy fix. I have visited MTN stores and thank MTN Constantia Cape Town for continuing trying to resolve the matter, but like myself get zero feedback from MTN head office on the issue. I was told in May by the same shop that my existing paid up account failed getting past the ***** check, this raised red flags and I had every Transunion type check done on my ID and name and shared the results with MTN as they were all clear, again no response. I often get sales calls from MTN wanting to upgrade my account which is very frustrating as they then realize they cannot also fix the bug / account defect. The frustration is the simply lack of response to their own MTN shops or my recent letter of complaint.