Not releasing my deposit paid for a rental car

I have been waiting for my R2105.24 deposit to be released by FNB for a while now. I rented a car on the 10th of December and paid the deposit with my cheque card. I had the car for about 4days. I am not phoning FNB again as I believe I am now officially in the stage where any queries will result in a shifting of goal posts. You know :'wait 2 days sir'. In the meantime they are making 0 attempt to contact me back, send me updates or resolve my query.<br> <br> They are doing nothing at all.<br> <br> It is my money, not credit or borrowed money, what is the issue?