This number calls and wants to you lower your interest rate on a credit card. I ask them which of my cards they were calling about and they just name off random ones like "Visa, Materscard, Capitol One." My guess is that it is some sort of scam because when you call them back it is a non working number.

Answered and nobody was on the other end.

Picked up, message said press 1 to speak to operator regarding lowering interest on your credit card.  I pressed one, was transferred to operator with an undetectable accent.  He said you contacted us regarding lowering interest your card.  I said,  which card is this?  He says, your VISA MasterCard.  I said, I have no balances on my cards.  Silence.  Click.  Dial tone. Call ended.

515-460-2739
Called back comes up invalid number. Scam marketing call probably. Install mr number it will be blocked.
515-460-2739

This is a scam call trying to steal information.  Do not give it to them.