Incorrectly debiting my accounting.

I was behind with my nedbank personal loan, made an arrangment of which i honored, my payment is scheduled for the 26th of each month. 26th came and the arrangement and payment was deducted. On the 28/03/2015 a debit order when through with Ref: Payment. I immediately went to the bank all to find out it is the Nedbank Loan. I called the Head Office and was informed the Collections Department is closed and they will call me back on the 30/03/2015 I never received any calls from them. I actually decided to call again (ref ***)today the 01/04/2015 and they telling the same story of 3-7 working days. And this is not even an option as the money in my account was reserved for other debits order. Which did not go through cause of Nedbank error. My ITC is affected how will Nedbank solve this inconvience. Can somebody at Nedbank pls solve this issue as I need the money urgently.