debit order not being submitted

I have opened an account in April arranged a debit order payment for the last payment every month, I made an advance payments and all along they have incorrect banking details. I contacted them to correct the matter, still after the matter they did not debit , collections department contacted me regards with the payments and we arranged R1000 that was debited from my bank account, and the following month they did not debit and I phone them, and they said the payment does not include advance payment and I am not behind with payments but the arrangement I made automatically cancels the normal monthly debit order, I made payments on the 1 Sep EFT ref I used my ID number , and till today they have not received the funds telling me I should use the card number. I am receiving calls for not making the payment but the debit order was never submitted and they admit it was not submitted, now this is affecting my credit score , very much inconvenience. I need help guys with cotton on and RCS Cards