Hi @Ana Llabrés
Changing a user's role in a team can be done through the Azure Active Directory. To do so:
- Go to https://portal.azure.com/ > Manage Azure Active Directory
- Click 'Users' and select the user you want to change the user type.
- Click Edit. Under 'User type' choose between member or guest then click save.
4.In Office 365 admin center > Users. Make sure Teams license has been assigned to this user.
The change may not take effect immediately.
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