Nedbank Credit Card distaster!!

In December I transferred money into my credit card that left me with a large credit. When I tried to use the money I got a message saying validation error. When I called the call centre, they could not explain why I could not get my money. I had to wait days for IT to sort it out. This month the same thing has happened. I am unable to access MY MONEY and Nedbank cannot tell me why!!! This is ridiculous. Seriously thinking about closing my account and moving to another bank.