Found this number on my caller ID

I am being harrassed by this phone number 7 days a week at all hours of the day, starting first thing in the morning till late evening.  When I try to call them back, the number rings busy, or will not connect.

Who are these people.  I want them reported.

The company is Level III communications from New Jersey.  You can't call them back.  They are harassing me too 7 days a week.

I have gotten 5 phone calls from this number today and the day is only half over.  I called it back once and it said to press 2 to be placed on the do not call list.  I called it back another time and it picked up and no one said anything, then it hung up.

This number keeps calling and I answer they don't say anything. And then I call back and they hang up