I've been getting this number during work hours for the past two weeks or so. They never leave a message. Home sick today so when they called I answered. The man on the other end is not calling from the Philadelphia area and tried to give me an 800 number to call him back on. He would not state why he is calling me which I thought was bizarre. When pressed about why his number is registering as a Philadelphia-area number he actually became agitated and rude.

Lots of calls to my parked DID.

It's a collection agency.  Source: Level3 fraud dept.

This number calls my business several times a day and just hangs up when we answer.

Pick up and nobody is there.

This number calls me once a day but no messages are left and if answered no one speaks.