CGM Signal Loss: What to Check First
You open your CGM app for a quick check, but the number hasn’t updated. It’s unsettling when something you rely on suddenly goes quiet. Before assuming the sensor has failed, start with the phone’s distance, Bluetooth connection and app permissions. A few checks can help you work out what’s happening without changing settings at random.
Check the message and the last reading time
Read the app’s message and check when the last glucose value arrived. A connection warning needs different action from a warm-up countdown or an instruction to replace the sensor.
An old number isn’t a current reading. Use your blood glucose meter for checks while CGM data is unavailable, as recommended in the ADA’s diabetes technology guidance. If you feel unwell, check promptly rather than continuing to troubleshoot first.
Check Bluetooth and app permissions separately
Make sure Bluetooth is switched on, then check that the Ottai app has permission to use it. These are two separate settings: Bluetooth can be enabled on your phone while access remains blocked for an individual app.
You can cehck the setting icon on the right top of your Ottai App, and choose permission management.
If the readings show Low or a flat line
A “Low” reading or a flat line does not necessarily mean your sensor is faulty. During the first 1–2 days, your body may develop some inflammation around the sensor, and white blood cells in the area may interfere with its ability to measure glucose.
If there is no system warning, leave the sensor in place, as readings may return to normal within a few hours. Contact our customer support team if the readings remain consistently low, no readings appear for more than 12 hours, or the app displays a sensor failure warning.
Know when to contact support
Contact Ottai support if the basic checks do not restore readings, the problem keeps returning, or the app directs you to seek help. Have the exact message, last reading time, sensor identifier, phone model and app version ready.
Avoid deleting the app, unpairing the sensor or ending its session unless the device instructions or support team direct you to do so.
Once readings return, confirm that the timestamp keeps advancing and new values continue arriving. That tells you more than a Bluetooth icon alone.
A missing update doesn’t automatically mean you need a new sensor. Start with the simplest checks, keep your meter available, and work through one possible cause at a time.
