Sensor shows Offline

Offline means no recent reading has reached the cloud. Newly registered sensors stay Offline until the first cellular send.

Checklist

Open the device page. Check last reading, battery, and signal.
If the sensor is off, open the lid. Press and hold the button for 1 second until the LEDs start to blink. See LED and button.
If you are next to the sensor, use Bluetooth Reconnect to restore NB-IoT settings, then wait for a send.
Weak signal is rare on NB-IoT. If it happens, try another spot. Leave the probe on the load. See network coverage.
Low battery: batteries cannot be replaced on site. Send the device in. Low battery is seen over Bluetooth or NB-IoT.
Confirm the QR you scanned is this sensor (serial and PIN).

If the phone sees Bluetooth but the cloud stays Offline, the radio path is cellular. See how sensors connect.