Click on this link to learn how to set up Family Sharing --> Set up Family Sharing - Apple Support
Read the section: "Invite people to join your family"
If something changed in iOS 16.6 then you are the first and only person to have observed that and mentioned it here. If the procedure in the support article does not work, contact Apple. If you still have questions or problems:
Refer to this document for ways to contact Apple ➞ Choose your country or region - Official Apple Support
Select your country (also look for "other" regions), then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.
or:
Contact Apple for support and service by telephone ➞ Contact Apple for support and service - Apple Support