Adverse information on credit

I have had contract with MTN for a number of years. I have never missed a payment, which was always deducted via debit order. I took out a new contract at the branch. My debit order was cancelled without me ever having missed a payment. I have been struggling for months to have it reactivated, I go to the branch to make monthly payments. Each time I call customer care since last year I am informed that the debit order has been reactivated, but it never deducts. I am now listed at the ITC as handed over, which has seriously affected my credit rating. Last month I made a payment at the branch I insisted that I was informed my account is in arrears and I want to pay the outstanding balance I was informed that my account in not in arrears my next payment due is end of March? I then proceeded to pay extra onto the account? Last week I was informed again my account is in arrears I made arrangements to deduct the arrears immediately? It does not even seem like my payments are being reconciled to my account timeously. This is unacceptable, I will never ever take out another contract with MTN as service provider. I have emailed numerous times to have my ITC updated with the relevant credit bureaus. When I called customer care last week they said that I am not handed over because they would have had to transfer me to the collections department and that I should update my ITC? How ?? I need this resolved on the credit bureaus as a matter of urgency, It is absolutely disgusting that MTN does this to people's livelihoods!!!!