Thrifty car rental NOT refunding holding deposit.

I have never been this upset and frustrated with a company ever. It is completely unacceptable to hold on to a deposit for car rental 3 weeks after the car was returned completely unscathed. I rented the car in East London on 27 Oct 2021 and returned the car on 30 Oct 2021. I started requesting the deposit refund to be returned to me the following week. Eventually on 11-11-2021 I had the 1st email reply confirming the refund process was done and will take 1-3 Business days. It is now almost the 5 full business day and still no refund of the deposit. I have emailed *** and the other 2 holding emails. As well as refund email and customercare email. No one responding at all. It is a R6000 deposit. It is absolutely ridiculous and unacceptable that a company can function like this. Truly pathetic