Billing me for non existing accounts

I had two accounts at MTN on my name for my two sons. When we wanted to change to Telkom we went into the Kolonade branch to enquire what the neccessary steps would be. I was informed that the accounts had been closed and that the only outstanding amount was the last debitorder that had to go down from my account Four months later MTN started deducting stoporders from my account No explanation or call was given The amount that is deducted is never the same Every time I have to go to the bank to reverse the payment. I have tried numerous times to contact MTN and could never speak to a manager or resolve the matter. The manager at Kolonade informed me that they have contacted MTN but can"t do anything as the account has been closed. Today I received an sms stating that I still owe money. When I phoned the consultant of MBD INC she put the phone down in my ear!! I have tried everything to resolve the matter. Can you please act upon my behalf!!