I got the call from the same # when you call the # back .. it is no longer in service. If they call and you have chance to speak with them get all their information and call local authority.
Its not polite to call my phone and hold it while I'm constantly saying hello. U r so childish and a coward to hold the phone to listen to a person say "hello" and then u hang up.
I sometimes think people like this call just to see if they can get a "live" phone number to sell to other people. The only remedy is not to pick up the phone if you don't recognize the number. And don't ever call back a number you don't know if it hangs up in mid-ring, to create a missed call.