debt collection harrassment

I have been harrassed for over 2 years by agencies looking for a Chad/Theresa(Teresa)Green or Theresa(Teresa) Johann. The Johann is the latest name they are looking for. I have had the same experience of them thinking I am Theresa or that I know her/or where to find her. I have had my phone number for 51/2 years. When I told a young female employee from some company that I was tired to telling these agencies that I am not the party, she implied that her company had just gotten the debt and if I would ask nicely I wouldn't have this problem. I am pretty sure the latest caller is from Allied but I am not sure of the full name. The reason I know this much is because I answered my phone and heard a message saying this is Allied... trying to collect a debt and to hold on for a representative. When the employee came on the line I asked who they were and could I talk to a supervisor. The hung up on me but I still get 3 or more calls a day from this same number and no message is left when the answer machine comes on. They are calling from 866 825 4574. If this is not Allied , do you know who it is and what I can do. I have also been told when you look up my number, you find Chad?Theresa Green referenced with it. The last time I checked that was not the case. Thanks for your advice.