AIRPORT RENTALS

I made a reservation through Airport Rentals on 23 September 2020. The full amount was deducted from my credit card. At the airport I collected a car from Avis/Budget. A few days after the vehicle was returned another amount for rental, fuel, etc was debited from my credit card. When I looked at the invoice it was not the same return date or the same vehicle. Budget/Avis are not assisting. How do I get my money back? I will NEVER use Airport Rentals, Budget or Avis ever again