Welcome to Microsoft Q&A Forum.
Thank you for reaching out regarding the issue that searching users in Microsoft Teams by their display name.
Based on my research, Microsoft has confirmed an ongoing service incident affecting Microsoft Teams (Issue ID: TM1212728). A recent change to our Active Directory service introduced a regression affecting user search functionality. As a result, users attempting to search new users in Microsoft Teams by their display name may be impacted.
For your reference: Service health - Microsoft 365 admin center
Note: Access is limited to Microsoft 365 Global Administrator. Please contact your IT admin if you don’t have access.
This incident is fairly new, and Microsoft is updating about this issue promptly via Service Health. Service availability is steadily improving toward normal levels, in the meantime, I’d suggest searching new users using their email address, since it still works according to the incident report. Just a heads-up: as a forum moderator, my testing environment is limited, and I cannot access to Microsoft’s internal databases to dig into the root cause of this issue.
At this stage, no action is required on your part. Once systems are fully restored, Teams should begin functioning normally again without the need to make changes to your settings or devices. That said, I kindly hope you can remain patient a little longer while the engineering teams continue working hard to fully restore the best possible experience for all users.
Also, since many others in the community may still be unaware of this incident, if you found this information helpful, please mark the answer as “Accept answer”. This will help surface the post to the top so others facing similar issues can easily find it.
Thank you again for being part of the Microsoft Q&A community. If you have any further questions or updates, feel free to reply here. I’ll be happy to assist further.
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