Pathetic service

Tonight I went to pick up my car rental at 1st car rental. I parked the car left my daughter in it as I just wanted to pick up the rental as I entered 1st car rental my daughter called me to say they just clamped the wheel. I went to avis to advice them that I have not been standing there for 10 or 15 minutes can they please unclamp my wheel as I did not know I will be clamped for parking therefor I left my daughter in the vehicle as she can drive. The manger on duty refused and said this is all on me I must go inside the Capetown airport and go draw R500,00 then she will unclamp my wheel. Saying if I rented the vehicle through avis they could've assisted. I did not rent the vehicle my insurance did. How can you be so inconsiderate. I had to leave the vehicle there and must go draw money to collect only in the morning as I had to rush to work