Family Sharing of Apple News+

Sometimes it takes a while for changes to appear on other devices. Rebooting should have accomplished that so if it still isn't showing you should probably ask Apple what is wrong.

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