Hi Dinglest177,
Welcome to the Apple Community.
Apple Support have articles online that may help:
Update your Apple Watch
(NB: Scroll to: If you need help updating.)
https://support.apple.com/en-us/HT204641
If you don’t have enough space to update your Apple Watch
(NB: You can check how much available storage your watch has,
by opening its Settings app, then going to General > Usage )
https://support.apple.com/en-au/HT211283
Also there is another discussion thread that may be helpful:
https://discussions.apple.com/thread/253392107
All the best :-)