Exceptionally disgraceful service by Telkom

I contacted Telkom to change my debit order date, this was done almost 1 month before the next debit order date. To my surprise after confirming with the consultant that the next debit order date will be according to the new selected date, my account still gets debited on the old date. This could have resulted in financial implications fro myself had there not been available funds in the account. When I called to rectify the matter I was advised that their system is faulty and the date cannot be amended. As a client their system issues is not my problem and I pay for the service. As much as the lady on the other side was apologetic and tried to be helpful, I cannot accept that negligence by the previous agent to advise details and capture it correctly should be the client's issue. Even when you want to pay your bills Telkom makes it difficult.