The Roost app will only let you Snooze if it detects you are near your alarm (within about 30 meters or 100 feet) when it is sounding. The Roost app relies on a GPS signal and Wi-Fi to determine your location. Turn on your smartphone's Wi-Fi and GPS so that Roost can detect your location with better accuracy.
The location limitation on the Snooze feature is so that someone cannot snooze an alarm without physically checking whether the alarm is a false alarm or an actual fire.
If your smoke alarms are connected to AC-power and your Smart Battery is being used for backup power, the Roost App Snooze button will not silence your alarm. You can tell if your smoke alarm is connected to AC-power by looking for an LED that is always lit on the outside of your alarm. If you see this LED, Snooze will not work.
The alternate way to snooze a false alarm is to press the "test" button on the smoke alarm, which will also silence most alarms that are sounding.
Do not remove the battery to silence the alarm, as doing so can create a major safety issue.