Automated message about free security system for allowing an ADT sign place on my lawn. FAKE
Its a phishing robo caller, designed to find if a random number they call is answered or not. The automated system gives a prerecorded message about a product or service and tells you to press 1 for more info or press 2 to be taken off the list. If you press either, nothing happens and it hangs up. You have now just confirmed to them your phone is answered and you get put on a list thats sold to telescammers.
If you call back, an automated system only offers you to press 9 to be taken off the list, then hangs up. This also confirms that a valid number called back they'll use for future scams.