Harassing the wrong person

This company has some how mixed my personal number up with some other random person. Now I get phone calls from them asking to speak to a person I don't know almost every day. Sometimes multiple times a day. This is interrupting my work phone calls and I'm not even the person they're looking for!!! I have told them over and over and over again that they have the incorrect number and yet still the phone!!!!!! I'm going completely insane!