REFUND OF AN INSTALMENT

I am renting a BAW Sasuka through Baw South Africa in Springs and on Friday, 27 February 2015 I made my first payment of R10 750. But when my banker did the transfer from my account the instalment was paid twice meaning R21 500 was mistakenly transferred instead of R10 750. My banker tried to reverse one instalment but she was unsuccessful. We then called BAW to make them aware of the mistake. They acknowledged that they could see that the instalment was paid twice, We spoke to two ladies namely, Khosi and Lebo. Khosi promised that the money will be paid back and she even took my banking details. After a week the money was still not in my account. I then followed up with Khosi and she promised to call me back. I was then called back by Lebo who told me that I will not be getting my money back. I will only get it back on the first of April 2015. I really have a problem as I need that money to do other things like paying my other accounts and buying food for my kids till month end. I also need to have a budget as I am now using the taxi money which comes in everyday and that will put me in danger of not having the instalment at the end of the month. Please help.