What it may mean

This message means your sensor could not communicate with your reader, app or smartphone.

What you can do

FreeStyle Libre 3 or FreeStyle Libre 3 Plus

iPhone:

Tap the scan button and try scanning the sensor again.

The NFC antenna is on the top edge of the phone.

Scan your sensor by touching the sensor with the TOP of your phone.

Move your phone around slowly if needed. Proximity, orientation, and other factors can affect NFC performance. For example, a bulky or metallic case can interfere with the NFC signal.

Android Phone:

Try scanning the sensor again.

The NFC antenna is located on the back side of most Android phones.

Scan your sensor by touching the sensor with the BACK of your phone.

Move your phone around slowly if needed. Proximity, orientation, and other factors can affect NFC performance. For example, a bulky or metallic case can interfere with the NFC signal. Make sure you are not touching any buttons on the phone or the screen.

FreeStyle Libre 2, or FreeStyle Libre 2 Plus

Try scanning the sensor again. Make sure to follow the directions in the "Starting Your Sensor" or "Checking Your Glucose" sections of the User Manual of your system.