MTN Again

After bungling up an upgrade which had been cancelled, it took four months for Mondo/MTN to finally accept that they had made a mess. An apology was sent and we decided to move ourselves away from MTN with whom we had been with for 30 years. We then had a call from a retention staff member who offered us a good upgrade. This upgrade occurred on 27th May 2027. We have just received an account from them which does not tie in with the contract we entered into with them. We have 3 numbers on the contract. 2 of the numbers were correctly accounted for with the new contract but one of the numbers is being charged on the old contract. I have spoken to their accounts and call center but they are unable to help me. They advised I send an email to the complaints dept. This I did yesterday and still have not received a response from them. Today I sent an email to Thandeka Ndlovu who was the person we dealt with regarding the upgrade and she as well has not responded. This is very frustrating. Our contract is for R594.00 per month covering all 3 phones. Its for data only. No new devices were taken. The account I have in front of me says we must pay R1412.99 which is totally wrong as it includes R736.00 which is incorrect i.e. the old contract amount. There is also an amount of R155.65 which MTN says was a self service purchase service. I asked the accounts dept on what date it was purchased and they said they can't tell me. The account itself also does not specify the date either. I checked with my family member who said he did not make the purchase. Today I received a message that said I must pay R594.00 as the debit order was not taken off. However the account as said above is for R1412.99. I am loath to pay this amount as overnight they might take the R1412.99 off for which I would probably never get the money back.