This number keeps calling and never leaves a message. Must not be important.

This number has called 10 times starting July 13th. Never leaves a message.

Caller calls 3 or 4 times a day, every day. When the caller gets an answering machine, he just hangs up. The caller asks for the party by name, but refuses to identify himself. When you ask to be put on the no-call list, he hangs up on you. When you try to call the number, it purports to be out of order or not in service.

never leaves a message I am on the do not call list

This caller is supposedly from some company doing free roof inspections.  He wanted to know if I'd be available for 10 minutes either Wednesday or Friday.  I told him I wouldn't and he just hung up on me.