If you frequently see "Sensor doesn't fit" message on the display, you can tighten the strap a little, to a comfortable position. The band’s sensor needs to stay in close contact with your skin, but it should not be so tight as to hurt your wrist. Please check the position of the band on your wrist - it should be placed 1-2 fingers away from the wrist bone (see the photo below).
Please note that any skin imperfections, such as scars, tattoos and even extensive hair growth can prevent GoBe from establishing proper contact with your skin. In this case you can try wearing GoBe3 on the other wrist or turn it on the inside of your wrist, find the most comfortable position and check if there is any improvement.
If the above recommendations don't help (or are not applicable to your situation), as the next step, please try cleaning the sensor of the device.
To clean the sensor, you can use surfactant dishwashing liquid or liquid soap: apply a small amount of liquid on the sensor, rub it lightly (you can use a q-tip), then rinse with water and dry with a soft cloth or paper tissue.
During cleaning, please avoid washing the charging cable contacts under running water, as they are not waterproof.
It is important to clean the sensor at least a few times a week, especially after any physical activity. This will ensure good contact with your skin and more accurate readings.
If after cleaning the sensor the issue persists, please observe if the contact with the skin is lost in a state of rest or in motion (when the hand on which you wear the band is moving).
1) If the contact is lost in the state of rest, please try moisturizing the skin under the sensor with water and keep wearing the band for a few hours. Check if there has been any "sensor doesn't fit" alerts during this time. If this helps the problem, the general recommendation for you would be to moisture your skin regularly, as excessively dry skin can prevent the sensor from establishing contact with the skin.
2) If the contact with the skin is lost in motion and you have already tried fastening the strap a little tighter and moving the band higher up on your wrist, most likely GoBe's geometry doesn't fit you hand, which happens if the wrist is too narrow. To confirm this is the case, please send us a couple of photos of your wrist with the band on it. Preferably, the photos should be taken from 2 angles: one from from front of your wrist and one from above.
We hope these recommendations are helpful! If you have any questions, please email us at firstname.lastname@example.org We will be happy to help!