"Not found" when accessing an organizations' site

[Ra Jo Ga Cha，修改在6 年前。]

This is in 7.0 GA3, clean installation. I created an organization which creates it's own site, and I can access that site with a superuser (p.e. test) but not with a normal user that is in the organization and without any organization role. I try to go into the organization and Liferay returns this in screen:

Status
Not Found
The requested resource could not be found.

http://x.x.x.x/group/control_panel/null

[Samuel Kong，修改在6 年前。]

The URL you're going to is not a valid URL, so the error message that you're seeing is expected. Even if an administrator goes to that URL, you'll see the same error.

[Ra Jo Ga Cha，修改在6 年前。]

It's how the error looks, but the strange thing is that I'm trying to access the site in the same way with each account:

Liferay [Site] - Go to other site - OrganizationSite

This works for Test but not for a standard user which is part of the organization

Edit: Error disappeared with 7.0 GA4.