I just received a second call from this number- usually no message us left. I answered it and the caller asked for ne by my first name. When I asked who it was, I was told the Kirby company.
When they call they are trying to find out if your number is valid, who answers the phone and when. They are either trying to get a phone list of valid numbers and info for their own use, or harvesting same to make a list with info for sale to all kinds of scammers. This phone # may actually a fake number used in common by different scammers. In any case, do NOT answer (verbally), do not press any keys, do not call it back, and certainly don't "press 1 to be taken off the list". Pressing 1 will put you on a list of numbers that DEFINITELY work and you'll get endless calls from all scammers.