I have hired a car paid the amount that was required and they took a payment from a credit card of R5000

I have hired a car paid the amount that was required and they took a payment from a credit card of R5000. And then I returned the car exactly the way it was when I took it for my refund of R5000 to be returned after 2-3 working days as they have said. After a millions of calls after almost 20days they again took R4 800 they refund me R200 and for what coz that's is *****ulent why did they take my money