As an admin/group manager, I created a level 1 user profile for one of our employees, but cannot add them to a group.
Organization > user's profile settings > Add to groups ....... gives the error pop-up above.
This is a new user and not part of any other group on the Portal.
The Group settings are: Open to Everyone (public) and 'Those who request membership and are approved by a group manager' can join.
I have verified the level 1 role permissions are default. Organization > EDIT SETTINGS > Roles "Viewers consume the resources of the portal. They can use the portal's maps and apps to explore data and join groups to access content shared to the groups."