To troubleshoot the issue, you could try accessing the Azure DevOps organization outside of Teams, using a web browser or the Azure DevOps desktop application, to see if you can establish a connection. If you're able to connect successfully outside of Teams, then the issue could be with the Azure DevOps application in Teams. If you're still experiencing issues outside of Teams, then the issue could be with the Azure DevOps organization.
If the problem only occurs in the Teams desktop client, I suggest you clear the Teams cache or update Teams to the latest version.
1.Clear Teams cache:
2.Update your Teams if your version is not the latest.
At the same time, in order to better help you solve the problem, I suggest you add the Azure and Teams development tags to your post.
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