My bank has left me in the cold through Dec & Jan

On the 17th Dec 2014 my wife went to withdraw money from a Nedbank ATM. Some random guy tried to press a button on her left, and as she had already entered the PIN on the machine, when she tried to cancell the transaction, the card was retained by the ATM. When I got there and went to block the card, I was given a new one and went to withdraw with it, and couldn't because of my limit. We went inside the branch and were told that I had withdrawn R12000. I reported the matter to the police and the case number was given. My daily limit is R5000. Statement shows that our money was withdrawn on different dates, although I was told on the day of the 17th that all the money had been deducted on the same day. I've been waiting for my money to be paid back by the bank, as proof was there that I hadn't withdrawn the money, but was de*****ed. My limit was bypassed and up until now, the bank has not refunded us the R12000, although we provided every proof needed that this was *****. How long does it take for the bank to give us back money taken **********ly from them?