Called about duct cleaning. We do not have ducts!

OBSCENE CALL .......Stated he was calling from a duct cleaning company & when I expressed I did not require this service he asked me if i wanted to suck his $%^&

For about three years now, the clowns peddling duct cleaning have been calling.  Every time they call, I ask/tell them to take me off of their list.  Obviously they don't give a damn; they just called again!