i got a message from an Erin re:someone i have not spoke to in 20years.didnt call back

Company is Alliance One, a collection agency. Call me every few days but do not leave a message. Finally they called very early on a Saturday looking for my brother-in-law (who lives half a country away from me). Lady on the phone was named Erin. While she wasn't harassing me she was very pushy about me giving her information to my brother-in-law. Sine I had only had a few hours sleep she got to deal with me being more then a little crabby. I told her that he did not live with us and that she had no business calling my house and expecting me to pass her message along just because she cannot get a hold of them. After a few moments of back and forth arguing I told her I would pass the message only if she removed my number. I told her if she called me again I would report her because this has nothing to do with me or my husband. We will see if the phone calls stop.