Sani car rental deposit refund missing

I rented a car in Johannesburg for the weekend of the 4th June. I took out comprehensive insurance however was still forced to pay a deposit of R3800. I was told that the refund would be paid within 7 to 14 days of the rental. It has now been over a month and Sani are giving me the run around. They don’t answer their phone and my emails state that they will get back to me after they have spoken to the audit department. This is completely unacceptable and basically dishonest. NEVER USE SANI CAR RENTAL. They are dishonest