Can I have my money back please?

I have a personal loan with FNB which I have been paying off accordingly ever since I started working again. Last month I instructed FNB to deduct the outstanding balance so that I could close the account. What they decided to do was to go into my account and deduct the monthly installment and then deduct the outstanding balance the very next day. In January they did the very same thing, they double deducted on my account, I had to call them and fight to get my money back, however this time it seems like I am not winning. The first deduction went off on Friday the 27th, the second went off on Saturday the 28th. This was not supposed to happen as my outstanding balance included the installment. To this day they say that my payment has not updated on their systems and they cannot refund the over-deduction until my payment updates on their side. It's been 4 days now and counting, and they still can't help me. I mean, even transferring money from one bank to another doesn't take this long! I have been making numerous calls to the FNB Legal call centre since Monday to no avail. FNB, can I have my money back so that I can move to another bank that won't do as the please with my funds?