Recorded message about air duct cleaning service.

They call here at least twice a week pushing for air duct cleaning.  I press ONE just to take their time and never hang up until my phone cuts out,..  It's obvous the the DO NOT CALL registration is an inaffective.  It should also be noted that they never mention a company name that they represent.  Phisers, I suppose. Or a band of gypsies.

Duct cleaning scam, when asked for a business name and a business hour phone number the lady on the other end terminated the call without response.

Telemarketer representing "California Heating and Cooling". When reminded the representative that I am on the  do not call list, person hung up.

This cleaning service calls many times a week! It's a recording, the first part of which is cut off.
I have reported them many times to the CA State Attorney's office.  What now?