Avis & GL Attorneys

I rented a vehicle in August 2022 from Avis. I am also a Presidents Card holder at Avis which means all my details and payment details are on Avis's system. So in March 2023 I get an SMS to which says the following "Dear ...... , Urgently pay your Avis Receivables acc with Pay@. Use Ref: ...... Check convenient stores on.." and a link to the payment Paypal. I think its a **** as how could I possibly owe a car hire company money for a vehicle when you have to supply your credit card details prior to booking and collecting the vehicle? After receiving many such SMS's which I think are spam I call the toll free number that goes to a debt collection company by the name of GL Attorneys. They cannot tell me how I managed to collect a vehicle and use it without payment but they are wanting me to pay immediately. How the f..k do Avis not simply contact me as soon as I returned the vehicle? instead they hand me over even though they have all my details? It's an absolute disgrace. To this day I have not heard a word from Avis who claim they tried to call me once in March 2023 and I never answered.