Asked for the owner by his first name (he does not use it) I said, Not here and hung up.
They came up Service Message on the caller id.  No idea who they are.

Continously call no one on the other end of the line

This number called our office and before anyone spoke, there was static and weird click.  The conversation went like this:

Man: "May I speak to the person in accounts receivables?"
Me: "I'm sorry that person is not available."
Man: "Ok..." click.

I did *69 just in case I was wrong to stonewall this person.