MTN not resolving an issue

I am not happy with MTN's service at the Jacqueline branch in Alberton. There was an issue with how the contract was handled and over a minor discrepancy on MTN's side they did not implement the black Friday deal to the number nor did they ever mention that there was a discrepancy to be corrected. Now 1 year later I find this out and they say there is nothing they can do. This is not good enough. I am disgusted.