Protected page not showed

Hello,

I have a page with is protected and visible to the group ‘member’.
I have a admin user which is added to the group ‘member’ but when I’m logged in, the content is not shown, instead i get the message ‘You need to login to view this content. Please Login. Not a Member? Join Us’

I’m definitely logged in, I can see the admin bar and are able to acces the backend.

I disabled all other plugins, deleted all users and other pages and activated the default theme ‘twenty twenty’ but still no luck…

I also checked the post and page tab to change the protected status in bulk, no change.
There is no caching plugin used, also no caching on the server.

What else can I do?

The page I need help with: [log in to see the link]