Hi @Leandro Fua,
Thank you for posting your question in the Microsoft Q&A forum.
Regarding that your school change the subscription plan from A1 to A3 but you can't use team properly. I’d like to ask a few quick questions to better assist you.
Could you please share a screenshot of your current subscription? You can check this by signing in to your account at Sign in to your account, then navigating to: My Account > View Subscriptions
This will help verify what products and licenses are currently assigned to your account.
What specific error are you encountering when trying to use Teams? If possible, please include a screenshot of the error message.
Have you contacted your school’s IT administrator? You can ask them to reassign the license to ensure it’s properly applied. This often resolves issues after a subscription upgrade.
Your admin should check if the Microsoft Team enterprise license have been assign to your account or not
Go to Admin center > User > Active user
Then choose your account and check for the Microsoft Team license
If you’re unsure who the Global Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support.
Thank you again for your time and understanding. While my initial response may not resolve the issue immediately, I’d like to gather more details about your situation so I can assist you more effectively.
I really appreciate your patience, and I’m here to help. Looking forward to your response!
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread