Hello Jane Lin,
Thank you for contacting Microsoft Support!
I have tested the same Graph API endpoint in postman using delegated permissions and able to fetch the response. Please find the below screenshot.
It sounds like you’re encountering an authorization issue when trying to access the joined teams endpoint. Here are a few things you can check:
- Token Scope: Ensure that the token you’re using has the correct permissions. For accessing joined teams, you need the
Team.ReadBasic.All
permission. - Token Validity: Verify that the token is still valid and hasn’t expired. Use a tool like jwt.io to decode your token. This will allow you to see the token’s payload.
Hope this helps.
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