Motor Vehicle Solutions Mailed letter to my parents saying warranty was about to expire,they already had extended warranty Saint Peters, Missouri

My elderly parents received letter in mail stating their warranty was about to expire.  Letter had their vehicle on it and unfortunately they fell for the scam.  They called and gave them their credit card number and they were supposed to be charged something like $100 a month, they charged their card $2250.  When I saw the charge and called the # they could not look up their account by the account # that they had given my parents.  Even when you say cancel they continue to try to persuade you and trash the auto dealers, finally when I told them my parents had purchased an extended warranty at the time of purchase and threatened them with Better Business Bureau and reporting them to the Federal Trade Commission did they tell me they would give me a refund.  "Michelle" wouldn't even give me her last name.  The credit card company requires that I give them 15 days to see if they process the credit before they will reverse the charge.  What is our world coming to, how can people feel okay preying on elders.  Please pass the word on, I have warned my parents about scams for years but these people are pretty sneaky!