receive calls on a regular base from this number never leaves message

Calls several times a week.
Obviously selling something.

Calls 3 times a day, every day, never leaves messages, and when someone answers by mistake no one on the other end talks, just dead air.

We are on DNC list, there is no reason for these calls. Anyone finds out who they are, let me know so we can put an end to these idiots.

Has been calling sevearal times a day for last couple of weeks. No message

they called and I decided to pick up. When I said "hello", there was no immediate response so I hung up quickly. Just as I hit the button to hang up, I heard someone begin speaking and there was background noise like in a call center.