Sounds like some group saying they are a credit card services but really just Private Investigators calling you to stake you out since they know you picked up, are at home and it saves them time and money by Faking a Call for credit cards.
and I BET the contract with Social Services, as in Food Stamps and Welfare.
The callers are the drug-addicted "card services" scammers, who call us, pretending to be associated with our credit card companies, in an attempt to fool us into giving them our credit card numbers, so they can rip us off. People that have given their card numbers to these junkies have suffered severe financial losses. Beware of these lowlifes, and warn others, before they are cheated!