Service failure

The service from MTN call centre is by far the worst I have experienced. I have be struggling with the same query since Jan 15 and 11 months later still not resolve. I keep getting told that the call was miss logged, or wrong department got the complaint so did not action or they lost my paper work so i should resend, but now they lost it again. I have spoken to countless agents and get zero response to mails from any of them.<br> <br> When MTN took over my contract from Nashua Mobile they did not honor my contract details. I should be receiving 200MB data monthly but have not been receiving it since the move to MTN. I received monthly sms's from MTN advising my account has been credited with the 200MB yet it is not. MTN call center and stores advise there is not 200MB free data on my account and i should mail through my contract from Nashua as proof. I have done this twice as well as sent them the letter from Nashua confirming nothing would change in the move. I have been dealing with this since January and am getting zero assistance from MTN as they keep advising they cant find the contract. They received all contracts from Nashua mobile as well during the transition. Who can I contact?