Got a call from here but I didn't say anything - especially when my caller ID says "Name Not Found"
However, my guess is that this is a from a bill collector trolling around in their search for other people.
You know the type, "Can you get a message to XYZ?" Because XYZ used your name as a reference without
permission, defaulted, and then disappeared?
But what I usually do, in any case, is pick up and say nothing - a legit caller will start saying "hello? hello?" and someone using an autodialler to get to you won't speak because the lines won't connect UNTIL you say something. It's a great way to avoid overseas scam calls.