My Watch, Face Gallery and Discover missing in iPhone Apple Watch app

I am managing my Kids Watch SE from my iPhone with family sharing. My kid doesn’t have an iPhone.

I have the issue that in the footer of the iPhone app the 3 Tabs My Watch, Face Gallery and Discover are missing:

so I cannot create watch faces and I can not manage apps from my iphone.

At the same time I am not allowed to install all apps from the watch. On the watch it shows iPhone required:

As a consequence I cannot install apps nor create watch faces.

Can anybody help? Thank you!