Got call from this number didnot answer id unknown

I have gotten calls from this number so many times I've had to block it on my phone.  It's only on my phone so I still see when they call, which is at the very least bi-weekly!  I can guess...

Calls our place of business 4-6 times a day, never leaves a message.When I call back I get a recording that says... not a working number.

cell phone N J

Caller ID came up as New Brunswick Connecticut. I've been getting several of these lately showing different cities and even small towns. Most have been about automobile warranties ( It's a scam.)  They know what year and model of he car, apparently from public records,  . Sometimes when I have time, I'll answer  and keep them on the line, answering questions about the warranty, what it covers, past   repairs that I have had, and if those are covered.except.. Once he thinks he has me hooked, I saw it sounds good, but .........I don't own that car anymore.  The person is  then upset and angry because I wasted HIS time. If you have the time, lead them on and have fun, then let them down.