Harrassing phones calls to my parents home and mobile

Two weeks ago RAB began calling my parents number in an effort to locate me regarding a debt that say is outstanding and that I owe. I have since contacted them via phone and via email, and will be following up with a written letter this week to cease and desist contacting any third parties with this case. I stated on the phone that I did not owe this money and requested they send me official paperwork that states their claim. This was two weeks ago and I have not recieved any paperwork, yet they continue to call and ignore my email requests.

I have sent them notice of the Section 805 of the Fair Debt Collection practice and have repeatedly asked them to stop calling my parents and deal directly with me. I have complied and am waiting for them to provide proof. In the meantime, they must absolutely stop harrassing my parents, which is causing undue duress and stress.