Dear @HÀO TRẦN,
Good day. Thank you for reaching out to the Microsoft Q&A forum!!
According to your description, I understand that you are having trouble adding or removing students and teachers in a Class Notebook created in Teams.
Here are the ways for class notebooks created in Teams or OneNote (Online):
1.Sign in www.office.com and click the All apps button on the bottom of the quick launch bar on the left side.
2.Find Class Notebook icon under All apps tab and click it.
3.Click Add or remove teachers. Select the specific notebook you want to add or remove.
For reference:
Add or remove co-teachers in OneNote Class Notebook (microsoft.com).
Add or remove educators in OneNote Class Notebook
If you can't find the class notebook you want to add/remove a student/teacher in step 2 above, please do these steps:
1.Sign in your account in Teams and find the specific class. You can access the class and find the Class Notebook tab to check if this is the class you want to add or remove.
2.After we confirmed this is the class with that class notebook, then click on the three-dot button to click Add member.
3.Add the student/teachers you want to give them access to the class notebook. That is to say, all students/teachers you added them into this class will have the permission to edit the class notebook.
Please let me know the updates on your side whether it helps or not. If the issue still persists, please feel free to reply to me in the comment.
Hope you having a nice day and really much warm regards to you as well!
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