FNB delay with car rental deposit refund

I rented a car from.Dec 25th to the 30th and paid with my FNB card. Today is january 10th and i still havent received my deposit. The processing of the rental was concluded on January 1st. I should have my money back and the bank tells me to wait 38 days for a refund. what kind of nonsense is this? They were only to hold the balancs temporarily during the rental.