This is observed when multiple Kidde Alarms are hardwire interconnected (HWI) to your Smoke + Carbon Monoxide Alarm with smart features.

When a "Test" is initiated from your mobile device for your Smoke + Carbon Monoxide Alarm with smart features, all the interconnected alarms in the network are also tested. Notifications from your interconnected alarms are processed by the Smoke + Carbon Monoxide Alarm with smart features as "Smoke/Co at Unknown location". This is the expected behavior during an actual Smoke/CO event.