Welcome Jay_mas,
You'd want to confirm that you meet the requirements for sharing Health data: Share and view health data in the Health app - Apple Support
About Health sharing
In the Sharing tab of the Health app, you can share any data you have stored in the Health app with up to 5 individuals. You control what data you share, and you can change it or stop sharing at any time. If a friend or family member chooses to share their health data with you, you can also receive notifications when there are changes to their health data.
Here's what you need
- An iPhone or iPod touch with iOS 15 or later.
- An iCloud account with Health turned on and two-factor authentication enabled.
- The person you want to start sharing with must be saved in your Contacts with their iCloud account email included.*
*If you start sharing data with someone, removing them from Contacts doesn’t stop the sharing.
If you still are unable to receive the invite, despite the information above (and you meet the requirements), then it would be best to connect with Apple Support
Wishing you well, cheers.