Changing your number is no guarantee they won't call again. What they do is start with an exchange, such as 222, then do 222-1001, 1002, 1003, etc. They just hang up if they get a business. I know that because I had a brief job at Globe Democrat in sales and that's the way they worked it. We had the same problem with Thomas. I told them sternly that they were harassing us and that put an end to their calls pronto. Or request to be put on the no call list...they're supposed to comply.