Diagnosis
The sock is not getting a consistent pulse-oximetry reading, triggering a loss-of-sensor alert. This is a placement or signal issue.
How to Fix It
Remove the Dream Sock. Check the infant's foot. The foot must be dry, clean, and warm. Place the sock so the sensor window, a small raised plastic bump inside, is centered on the underside of the foot, just below the ball. The Owlet logo on the outside should face up. Tighten the sock until you can fit only one finger between the fabric and the ankle. A snug, immovable fit is required for the green and infrared LEDs to penetrate the skin.
If That Didn't Work
The infant's movement is disrupting the optical path. During active awake periods, the signal will drop. Disable notifications for awake times via the app. Go to App Settings > Notifications > Alerts. Toggle off 'Awake Time Alerts'. The base station will still sound for a 'No Signal' alert, but this separates movement-based false alarms from sensor-off events.
Heads Up
If the base station shows a steady blue light but the oxygen reading is still dashed, the sock is on but not transmitting data. This indicates a Bluetooth link failure, not a sensor issue. Power cycle both the sock and the base station.