Ultra 2 Apple Watch Wrist Detection/Activity Failure

My Ultra 2 Apple Watch is no longer detecting my wrist to monitor my heart functions (afib detection, heart rate, etc.) or stay unlocked to track my activities throughout the day/workouts. It has started to do this since the 26.5OS update. It would stop detecting for a small period of time, no lights would illuminate on the back side but usually would correct itself within 24hours without any participation on my part. For the last 5 days, nothing works. I have tried to reset, unpair, wrist detect turned off and on, run the battery all the way down and let it sit overnight to then recharge fully, etc. Nothing has "jump started" it to work again. Any other ideas?

I have an appointment setup with the Genius bar in 2 days but I am guessing they are going to tell me nothing they can do other than send it in and expect a $399 bill for repairs.

The Ultra 2 was purchased in November of 2024 and outside of Apple Care now.

Appreciate any help on this now $799 bracelet now hanging off my wrist that is useless.