Standard "air duct cleaning" scammer

got a phone call, just saying hello hello

air duct scammer, has been calling all week. I told him to stop calling - we'll see if he does.

Got a called today, left a message only, tried to call back but phone shows not to be in service

He probably won't.  We get a call every week and even though we tell him to take our number off the list, they don't.  Best thing to do is either say yes and send him to a fictitious address (make sure you don't pre-pay via the telephone), or tell him to wait a minute and you'll get the man / woman of the house and leave tem on hold forever.  They will hang up.  Either works sometime.  Good luck