Europcar did not accept my insurance letter and charged me 250 dollars for insurance that I had.

My credit card provides insurance for rental cars in Mexico. So I had printed a letter that I had received from my Credit Card Provider saying that the insurance will be covered by my Credit Card Provider. But Europcar did not accept that letter. They told me that you have to show an extra letter from Carta De La Comision Nacional De Seguros Y Finanzas. I told them that based on what is mentioned on the internet, a letter from my bank saying that my insurance is covered is enough, but they insisted that they will not give me the car if I do not buy insurance from Europcar. So I had to pay them 250 dollars extra to get the car.