Hello @Paweł Włudarczyk
Thank you for sharing your workaround and helping us understand the situation better.
I’d like to ask: have you noticed whether this issue is affecting other users in your organization, or is it happening only to you?
Based on my research, a few users have reported similar behavior and mentioned that using Microsoft Teams on the web helped bypass the issue. If possible, could you help confirm whether the same problem occurs when accessing Teams via a web browser?
If this issue is affecting multiple users, it may indicate an organization-wide provisioning issue. In that case, I recommend asking your IT administrator to:
1. Report the issue directly from the Service Health dashboard in the Microsoft 365 Admin Center. This helps Microsoft acknowledge the problem and track its impact across tenants.
2. Raise a support ticket directly with Microsoft via the Admin Center.
The Microsoft Engineering Team can investigate the provisioning logs and provide deeper insights. They are best positioned to assist with backend-level diagnostics and resolution.
When submitting the ticket, I recommend including a summary of the troubleshooting steps you've already taken such as creating a Class Notebook, adding a test assignment, and uploading a file to the Files tab. This will help Microsoft Support understand the context and accelerate the investigation.
Thank you again for bringing this to our attention and for working with us to get it resolved. If you have any additional questions, feel free to let me know. I’m here to support you.
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