Don't answer - spoofer. Block it. Whenever I get a call on my cell from an unknown number - I quickly dial it from the landline at work 99.99% of the time - it is a nonworking number or you get an automated answer about using any number to be removed from their call list. Do not do this. That only tells them that a warm body is picking up. These types do not care about laws and the do not call list. When you get a call from a nonworking number meaning a number you cannot call back or trace - it means a SPOOFER is on the other end. Resist the urge to pick up your cell phone just because there is a call.