Or you could use the option to be removed. I select it on all of these calls. Try it. It works. If I am bored, I  just keep saying "Hello" link I can't hear them. They eventually hang up. I don't get these calls. One time I am going to do something I read about and that is to answer and pretend to be a cop and say I am answering the phone at a crime scene and accuse the caller of committing the crime.