MTN must resolve the dispute on my account

Please can MTN resolve the dispute on my account. MTN is really not fair because there was an issue with my data which I was not able to use for more than 3 months. MTN knew this and kept transafering me to the next department everytime I called. I even wrote to MTN on twitter and by the time the matter was resolved, I had gone more than 3 months without internet. I refuse to pay this because MTN breached their contract by not providing the data. I did lodged a dispute and MTN dismissed it saying I have to pay in terms of the contract offering no explanation about the fact that I was not able to use data. Now MTN has *****ed my credit record and I am very aggrieved as there was ample opportunity to resolve the matter but MTN thinks they can bully me into paying the amount. Please can I be assisted by a senior person to resolve this issue and not all these *********** junior staff I have been talking to