If sleep data is missing, check whether the conditions required for the device to detect sleep (heart rate and motion measurement) are being met.

1. Check sensor direction and snug fit: Make sure the ring’s internal sensor (or the b logo) is facing the palm side (under your finger). If the ring rotates during sleep so the sensor faces the back of your finger, or if it’s too loose, it won’t be able to detect the blood flow signals needed for sleep determination and won’t record data.

2. Check whether other data is being recorded: If other biometric data such as heart rate or blood oxygen also aren’t showing, check that [Auto Measurement Mode] is properly enabled under [My Page] in the app.

3. Restore data and sync manually: Due to platform (Google/Apple) policies, background sync is restricted while the app is closed. In the morning, open the b.ring app and pull down on the home screen to complete a manual sync all the way through, or run [Restore Data] in the app menu.