Phone companies are considered "Common Carriers", with "open access".
Essentially, that means they are open to the public ... no discrimination for any reason, unless the company is notified by legal authority, after the customer has been found guilty of certain crimes.
http://www.cybertelecom.org/notes/common_carrier.htm

And .... it is not NSA's job to block calls from common criminals who are not endangering the national security.

The REAL answer is to buy a phone blocker ... particularly if the scammer is repeatedly using the same number!

Self-reliance is really not too foreign a concept, is it?

don't unswer.

called twice no message..

Caller ID shows from Newport TN this time.  I get a call from a different city about the same time every day.  When I pick up, it's some idiot robocall wanting to verify my Google listing.  Unfortunately, I have a cheapie cell phone with a number from some schmuck running an at-home business, and he probably scammed his clients, because even after a year, I'm still getting calls looking for this SOB.

423-248-2450 - Newport, Tenn.  No message