Adding existing teammates to user group triggers 5-user limit warning

Hi guys,

we're currently setting up our bitbucket account (using the free 5-user plan). We have 5 users in our team, but when trying to assign them to different user groups we are triggering the 5-user-limit warning and are prompted to upgrade our plan.

What are we doing wrong?

Attached screenshots of our users on plan and the dialogs to add one of the existing users to the administrators groups, which does not work.

Thanks a lot for looking into this.

Regards,
Michael.