altimeter on apple watch 6
The altimeter worked for three months after the purchase, and now it does not show the altitude. Resetting the settings didn't help. I use a watch with a silicone strap from the box. What to do?
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The first (and simplest) thing to try if something isn’t working right is to restart your Apple Watch and its paired iPhone. If necessary (device not responding), try a forced restart. Both methods can be found here:
How to restart your Apple Watch - Apple Support
Restart your iPhone - Apple Support
If that doesn't help, the next steps would be to unpair and pair your watch again and restore from the backup just created. This should result in no loss of data. It deletes all temp and corrupted files and re-indexes the file system.
Unpair and erase your Apple Watch - Apple Support
Set up your Apple Watch - Apple Support
Also from:
Use Compass on Apple Watch (Apple Watch SE and Apple Watch Series 5 and later only) - Apple Support
"Note: Compass won’t display elevation or coordinates if Location Services is turned off. To turn Location Services on or off, open the Settings app 
on your Apple Watch, tap Privacy, then tap Location Services."
