The solution is simple. The government needs to find out what telephone company provides service to this number and make that telephone company cut the service. They also need to put the subscriber on a "No Telephone" list, and cut the service to all other numbers they use.
I get these calls almost every day and I usually call back and get "dead air". Today I was lucky: National Geographic, calling from De Moinse, Iowa. It's a land line and Qwuest Corporation is the phone provider.
When I told them I want to be taken off their list, they asked for my name, which I would not give them (especially since I have an unpublished phone number). Usually, all you need to give whomever is calling you is the phone number they are calling in order to be removed from their calling list.
In any event, I filed a Complaint on the national (government run) "Do Not Call" registry. This is the SECOND complaint I've filed against National Geographic in the past 12 months.
I question whether these turkeys are indeed National Geographic since they call around the clock nonstop. My telephone number is on a do not call list but these jerks keep calling. I think its a con operation.