This company keeps calling and ignores Do-Not-Call-List requests. They become abusive when you ask them to stop calling and offering a free home alarm system. Caller ID says Iowa City.
The DNC list applies only to legitimate, participating telemarketers. Telecriminals (like these), do not follow it or any other laws. And---the more you engage them, the more they will call. Go here for a detailed discussion on call blocking devices:
http://800notes.com/forum/ta-5d4e343675a5629/call-blocking-devices