Problem with visibility in Navigation (Usergroups not working as expected)

I am very new to Softr, so I might have a very basic misunderstanding. I tried the search without luck and so I try it this way.
→ I want to control my content for specific logged in user groups. I assigned the groups and tried to set the visibility to only the groups I want the menu Item to appear. Result is, the menu Item does not appear at all, if I set the visibly to specific uaergroups. All logged in users the menu shows just fine . How can I debug this?
I am on the free plan, which shouldn’t be an issue.