Called three times. No voicemail. When answered, no response?

This number just called me. I don't know how they got my cell phone number, but I won't answer to them anymore.

I have received at least 2 calls daily from this number. Leaves no voicemail and I don't answer it, its not a number I'm familiar with.

They call several times a week, and every time I block a number they call from a different one - all identified by my phone as Keenesburg, CO.  Today they called from 0905, but they have used 720-580-0861, and 720.580.0861 that I know of.

SPAM ALERT!
Very persistent caller. Calls several times back to back. Finally decided to answer since whomever was on the other line doesn't give up, just to find that it's the same company that just called me last week cept the phone number was 720-580-0860. Same lady, Her name is Brooke and she's trying to fill a cruise ship.