Thrifty holds onto our deposit for more than 21 days !

We rented a car from Thrifty (Dollar) on the 16th of December 2022 at O R Tambo for just one day. Brought the car back - nothing wrong - just petrol to be filled up. Since that day they have been holding on to our R8220.00 deposit and not refunded it. I sent several e=mails and apparently, they cannot open attachments in order to look into my query. Yesterday I threatened them with FNB Visa Card ***** Division Today, after I copied them into my mail to FNB they said they did the refund, and it will take ANOTHER 4 days to appear into my credit card account. Do NOT make use of them. After my experience, I saw a lot of other people were complaining about the same problem. Other car rental companies do not even take a deposit, they just put a hold onto the amount and the minute you bring the car back, they just release the hold. Again, do not make use of Thrifty Car Rental