One possible reason is that the sensor may be under pressure while you're sleeping, which can cause the BUZUD CGM to report lower glucose readings. Once the pressure is relieved, the readings usually return to values that are closer to your fingerstick results.

To avoid this issue, choose a sensor site that is less likely to be bumped, compressed, or laid on during sleep.

If the readings do not return to normal after relieving the pressure, consider doing a calibration when your blood glucose trend is stable to help the system regain accuracy.