Bad service from MTN

My contract with MTN expired in July 2015. Initially I wanted to upgrade, but after not getting any feedback regarding the upgrade, I went to a branch to cancel the contract.<br> I never received any feedback.<br> After calling MTN several times to have the contract cancelled, I received an email from MTN's retention's department offering me an upgrade, I made it clear to them that I was not interested, I wanted them to cancel the contract with immediate effect.<br> It has been two months already and MTN has still not cancelled this contract and they still debit my account.<br> Despite numerous attempts to have the contract cancelled but MTN still does not cancel this.<br> What is it that I must do for them to cancel the contract because I have made it clear that I do not want the contract, I want it cancelled. My contract with MTN was for 24 months only nothing more than that.<br> I have written communication with MTN but they are still *******ly debiting my account as legally I no longer have a contract with MTN.<br> The reference number for the request is #***7