I didn't listen to the entire message, but it was "we have been monitoring your credit card activity for the past 6 months and if you are carrying more than $10k in credit card debt . . ."  That's as far as I went.  I received the same recording last week from a number in Kansas.

Called my mobile mid-afternoon. No CallerID. No message. Follow me on FB and see 15,000,000 Texas Militia take back the Lone Star State from the anti-Christians.

I never call back a number that I don't know or don't leave a message.
Calling back any number will tell the spammers it's a valid number ... never call a number you don't know!!
Caller ID said unknown.
call to my cell, how the hhhhhhhh do they get my cell, i give to no one, lousy jerks,do not know this area code, i goggled, an said it is florida, will not call them back, as u say,u call them back, an that gives the idea your number is valid, always google it, to see how many times it is pestering others,  too bad a block on numbers with att, cost a forever monthly fee also, as long aS YOU WANT THEN UMBER BLOCKED, ANOTHER SCAM TO MAKE ATT RICHER, NO COMPASION, ALL ABOUT THE MONEY FOR HTE CROOKED CEO'S

It doesn't cost money to block numbers with AT&T, at least not on your cell phone. Most phones have the option now to do that on the phone. Just select the number, and one of the options that comes up should be "Block"