Calls, does not leave message. No one there if I answer??

This number has called me for the past several months, however, I have never answered because I don't answer unknown numbers. They typically call twice leaving no message.

White pages reverse directory says its Margaret Nonato M PA at Sacramento St. Vallejo. No reports of complaints. Nonetheless I blocked this number on my cell.

Called on landline, recorded voice said, "Hello, my name is Joe and I'm with Veterans Now on a recorded line, can you hear me ok?". I said nothing and after about a minute the call disconnected. One minute after the call disconnected, another call came in from (626) 205-9630  ACTIVITY LEAGUE. That time I didn't answer and no voicemail was left.

Sounds like the scam described on TV news a couple of nights back.  The robot caller will ask if you - "can you hear me?"
If you answer in the affirmative "yes," that can come back to cost you big buck$.  Good for you for not saying "yes".
Folks have reported false charges on their CCs and other problems.
Now days we assume that every call is a scammer - unless we know the caller or the number.