I have received 2 calls from this number, I did not answer the 1st time, but my son was visiting the other day and I told him to answer the phone, and they said they were calling about duct cleaning, my son told them we had already had ours cleaned, the call was made at 9:00 pm, these jerks are relentless, just another call to block.
Wanting to clean your duct work; furnace. I've had this same Indian accent guy call a couple months ago, different number. Like many scammers, they probably change numbers every month or so.
I suspect that they might actually come out and clean you ducts, but end up ripping off the unsuspecting, like elderly; like telling them they've found all kinds of problems that will require more money, etc. JMO.