Debit order reversal a nightmare with FNB

I have called the call center agent's to have certain debit orders reversed to which I was told that the function was not available and I would be required to call the service provider to have the debit order reversed. I then visited the branch where I was told that the debit order reversal instruction needs to be given to a specific department where they will reverse as soon as possible. It is now a week and the debit orders still have not been reversed.