MTN DO NOT VALUE THEIR CLIENTS - ******S !!!!!!

I did an upgrade on my phone on black Friday. I found that I was not getting the correct amount of data, when I called in, I was told somebody will call me back to sort out. I have sent several e-mails and made several phone calls and to date I am still not sorted. I am paying more for my contract and not getting data and calls per my agreement of contract. One-person told me I did not upgrade on black Friday, another told me I did not upgrade, instead I took out a new contract. They clearly don't know what they are doing but this is affecting my finances and cannot accept this. I need them to fix this issue and refund me accordingly. Cell ***