DEBIT ORDER DEBITED PRIOR TO AGREED DATE WITHIN STANDARD BANK

They debited a debit order prior to the agreed debit date. Then when phoning the banking call center to reverse the debit order, I get told that they cannot reverse the debit order after spending 40 minutes with them on the phone. I only get told that the debit order (Which is for another Standard bank division) is system generated and cannot be reversed and they apologies. How can they not reverse their own debit orders ????? How does an apology resolve the issue at hand????? Been with them for over 15 years and this has just made me want to change banks now.