Unexplained Charge By Avis Rental

I rented a black Toyota RAV4 (plate FL6279AN) from Avis at West Palm Beach Airport under rental agreement 902052362 from September 14 to October 12, and then continued with a second agreement with the same vehicle from October 12 to October 31. For these rentals I paid $700.72 for the first period and $936.72 for the second period. Two days after returning the car, I noticed an additional charge of $173.82 taken from my debit card, as well as a $76 hold that is still pending. These amounts were not explained to me at the time of rental or return. When I went to the Avis West Palm Beach Airport branch, I was told that I needed to wait for a refund and that this could even take up to six months, which I find unacceptable. Since then, I have gone to the branch three times and have also contacted the manager, Hector G***, by phone and email. Despite these efforts, I have not received a clear explanation or a resolution, and the issue remains unresolved. I am requesting a refund of the $173.82 charge and the $76 held on my debit card, for a total of $250, and I also expect a clear written explanation of why these amounts were taken in the first place.