Welcome to Oros!Originally Posted by guest-ZVqvNGU9 Go to original post
My first suggestion to resolve this would be to power cycle your Xbox One, you can do this by completely shutting down the console and then unplugging it from the wall for a minute or two and then starting it back up. You'd be surprised how often this resolves the issue.
If that doesn't bring back your health bar please contact Ubisoft support and they should be able to help you out with the issue.