Auto-dialer will call at random times without leaving a message.  If you answer you get an aggressive and obnoxious sales pitch for chimney cleaning, but who knows what they really sell.  Have asked them to remove my name from their database several times, note I have never done businesses with them, they just ignore and call every year with their pitch.

I have received several calls with no one talking on the other end.

chimney cleaning company - sales call