Avis Kauai

When I arrived in Kauai to pick my car, I was told that I must take a $ 3000 insurance at a cost of $11.99/day. I protested, said I did not want, said I had a Avis reservation confirmation without such insurance. I was told pay or no car! With no other alternative available I Paid. I thought I had a valid quote, and Avis should return the fraudulently extracted money (10X11.99) from me. Never got the extra money back, nor did I hear from Avis.
Stan Chojecki