Another Avis client waiting for refund

Sadly I have to add my disappointment to the many others. Received car on 19 Feb. Exceptional treatment by employee who went over and above to supply the vehicle. Returned the car 24 Feb. And now Avis financial/admin staff is letting down the employee at the agency for not having refunded me my "holding deposit" to date. The money was actually not placed on hold but deducted. I have had enough back and forth explaining to Avis I want my money back I am considering other action. Unfortunately, the vehicle was booked through my insurance, and they are still waiting for me to rate Avis as a service provider. What do I do?