No idea who this is hangs up each time.

Constant calls from this number, usually do not answer and they never leave message.  I finally answer the phone and they hang up when I pick up.  I suspect they are a telemarketing company that verifies phone numbers before they sell the list.  When i called it back, I entered my number in to be removed from the Do Not Call list.  I am also registered Nationally with the Do Not Call Registry.  Caller ID stated it was from Newark, NJ.

Caller ID says it's Metro Marketing.