I get a couple calls a week from these types of scammers. Best policy is "if you don't recognize the number, don't answer." I just tap the volume button on the side of my phone to silence these types of calls. When I have time, I check here to see who called and at least 99% of the time it's a scam call. Then I'll listen to any VM that might have been left and delete. Most of these numbers are spoofed anyway and the scammers are mostly out of the country. They know the probability of them being caught are next to zilch.

I know mine is on the Scammer Hot List because I answered a call in my area code that turns out was a scam. This way the scammers knew they had an actual working number. Others will just cold call down all the numbers to find ones that  give them an actual ring instead of the   "Sorry, this number is not in service."

Do Not Call isn't a joke -- it's only valid for legitimate telemarketers which is why it's not effective. Scammers aren't legit in any sense of the word. I wish there was some other place we can report these numbers to.