Watch9 Missing Some Hours or Sleep Data Nightly

I am writing to request technical assistance for a recurring issue with sleep tracking on my Galaxy Watch 9. The watch continues to miss significant chunks of sleep data every night, leaving large unrecorded gaps and displaying incomplete sleep stage metrics (specifically Deep sleep and REM sleep).

Below is a summary of the troubleshooting and configuration steps completed to resolve the issue:

1. Fit and Wearable Setup: Switched to a Fabric Band to allow precise micro-adjustments. The watch is worn snugly about one finger-width above the wrist bone to maintain steady skin contact with the BioActive sensor.
2. Samsung Health Advanced Settings: Toggled on and verified all Advanced Sleep Measurement settings in Samsung Health, including continuous Blood Oxygen monitoring, Skin Temperature tracking, and Snore Detection.
3. Health Monitor Integration: Configured and authorized the Sleep Apnea feature in Samsung Health Monitor.
4. Active Sleep Profile: Consistently engage Bedtime Mode prior to sleeping.
5. Conflict Resolution: Executed a full factory reset on the previous wearable (Galaxy Watch 6 Classic) to remove potential sync conflicts or duplicate device bindings within Samsung Health.
6. System Permissions & Setup: Re-verified all background data, location, and health measurement permissions following the Samsung setup wizard.

Despite these steps, sleep logs routinely miss large portions of nightly rest. Please advise on how to proceed.

Thank you