Tracie, if you do not recognize the number or it is our of your error. 99% of the time it is a scammer. Do not answer it.
If it is important they will leave a message. and you can call back. If you answer it tells them that it is a good number and they resale your number to other people looking for numbers. I cannot believe it is worth the trouble they use call so many people who HATE THEM.
I sometimes answer these call and scream into the phone. ..."the job is done, there is blood everywhere, run, run run" and I hang up. Let them stew on that for a while. ha.
Somewhere in all these notes you'll find a post by someone who said pretty much what you did. The response was so just buy our service and we'll stop calling. Why they think that crap will get them business is beyond me, but we get at least one call per day from these non-Google AdWords assh****s, often 2 or 3. They have a lot of different numbers. Impossible to block them all. Aggravating as hell.
Indian and Pakistani web design SEO outsourcing spammers harvesting tel numbers off your web site trying to scrape up extra $$ for curry powder and noodles. Don't answer, it's telemarketing with a capital T. Also calling from 571-765-5576. Take a hike spammer, not interested in black hat SEO