Teams Education, Assignments and Grades not available

Hello all.

The subject says it all, last night in office 365 admin I try to limit third party apps in order to allow only Microsoft apps to my users.

Something I did wrong because now Assignments and Grades don't appear in Teams desktop app ou in web version.

I can see the assignments in Conversation chat ("Conversas" in my language) but Assignments or Grades aren't available to work with.

Something I did in the admin centre is blocking the application, I can see it briefly when I launch Teams desktop app and click it, only to see the message  "Esta funcionalidade não foi ativada para a sua organização" which says more or less that the app wasn't activated for the organization.

So, where in admin center can I activate this Assignment and Grade apps?

Thanks in advance.