i've followed the steps with my apple watch 3 to repair it to update, but it still won't update.

I understand A lot of people seem to be having problems updating the series 3 watch due to storage problems. You can try the steps in:

If you don’t have enough space to update your Apple Watch - Apple Support

If you still need help, contact Apple Support.

Updating an Apple Watch 3 is a bit more complicated than for the other models. Please refer to the steps in the following article: https://www.theverge.com/2021/5/4/22419569/apple-watch-series-3-software-update-reset-bad-experience

Perhaps this article will help;

If your Apple Watch isn't connected or paired with your iPhone - Apple Support

Excellent article! Thanks!

You are welcome!