Scammers pretending to be Google partners. You wouldn't be reading this if your telephone provider and government allowed you to block roboscam calls from ever reaching your phone. Blocking on your phone only hides future calls from that number.
They called and didn't leave a message. We've got so many calls this month from damn telemarketers. I just always let the call go to voice mail if I don't recognize who it is... if they are legit, they'll usually leave a legit message. Ya just gotta be careful about surveys, contests, etc. They're usually scammers too.