DIAGNOSIS The room sensors detect occupancy via motion, and they're not super sensitive by design—they're meant for walking through a room, not detecting subtle movements like typing or watching TV. It's likely working normally, but if it *never* shows occupied, there might be an obstruction or placement issue.
FIX First, check the placement. The sensor has a limited field of view. Make sure it's not tucked behind a vase, pointed at a wall, or placed above a doorway where you walk under it. It should be mounted on a shelf or wall, facing the main area of the room where people walk. You can also test it: walk deliberately in front of it from about 6-10 feet away. The green light on the front should flash briefly.
IF THAT DIDN'T WORK The sensor might need a re-pair. Go to the main thermostat, press Menu > Sensors. Select the problematic sensor and choose 'Remove Sensor'. Then, go to 'Add Sensor' and follow the prompts to re-pair it. This often clears up any communication glitches.
HEADS UP Remember, the sensor only uses motion for occupancy. For temperature, it's reading constantly. So even if it says 'unoccupied', it's still reporting the temperature back to the thermostat if you've included it in your 'Comfort Setting' for that time of day. Check your comfort settings in the app to see which sensors are active for 'Home', 'Sleep', etc.