Apple Watch ultra sleep tracking wrong

The basic first troubleshooting step with an Apple Watch is to un-pair and re-pair it.

Also, Apple doesn't read here for feedback. You can, however, let them know your thoughts here:

Product Feedback - Apple

I don't see anything about auto-detecting gym equipment.

Use gym equipment with Apple Watch Ultra - Apple Support

That article implies you need to hold the watch near the equipment. It doesn't sound automatic.

There is a setting "Start Workout Reminder" which will suggest you start a workout if it detects you might be running, walking, swimming, cycling or an an elliptical or rower. I've found it usually detects a walk within about 10 minutes (and them seems to backdate the start).

I like to track my sleep but, a couple of nights a week, I don’t wear my watch, to both give my skin a break and to completely charge it up. When I wear it to bed, I charge it in the morning when I’m getting ready for work and often don’t have time to get it completely charged.

It's a bit late but, if you only wear the watch to track sleep, I think you really overspent to buy the Ultra. The regular Apple Watch would have done just fine (and is smaller and lighter). But, if you're doing hardcore outdoorsy stuff on your days off, perhaps it's the right watch for you.

If anyone can tell me how to get more deep and REM sleep and less core sleep then I might try monitoring my sleep again. I don't see much point in measuring something I can't change.

I measure by blood pressure, blood glucose, resting heart rate, and cardiac fitness because I have means of improving it.

Here's an unconventional tip. Put the Watch on the night stand and get a better night's sleep, and rest your skin too.