You could not make them stop calling. We got a new cell phone with a new number and the calls started within 4 days. They even called on Christmas Day.
They've called me on my cell phone and on my home land line.
The intriguing thing is that the Caller ID has the call originating on several different 800 lines and on a broad selection of regular lines -- originating from different states, from Idaho to South Dakota, to Maryland, to New Jersey.
I've yet to see one repeat.
I'd wager that they've found a way to spoof the Caller ID.