My teams account is "unknown user" an not get accept with other user

Dear @Pham Sam,

I understand how confusing this can be. When your Microsoft Teams account is shown as “Unknown user” and other users cannot accept or connect with you.

In Microsoft Teams, this behavior can occur in certain scenarios by design. Specifically, users may appear as “Unknown user” in the following cases:

• When the user account has been deleted
• When the user account was disabled and then re-enabled

If the account has been permanently deleted, the display name will remain as “Unknown user” and cannot be restored, as the original profile no longer exists in the system. For reference: User appears as Unknown User in Teams

Note: If you are user, please reach out to your IT Admin to help you. For reference, please refer to How do I find my Microsoft 365 admin?

In this case, you can try to create a new account or restore user if that user needs access again. For reference: Restore or remove a recently deleted user > Make sure the account has a valid Microsoft Teams license.

If the account was disabled and then re-enabled, this is usually a temporary issue. In that case, you can speed up the resolution by asking the affected user to sign out of Microsoft Teams completely, then sign back in.

If possible, try accessing Teams from a different platform (for example, the web browser/another device) or try opening new InPrivate window to see if the issue persists.

After doing this, the display name typically updates within about 72 hours, although in some cases it may take up to two weeks for full synchronization.

However, if the issue still persists, to better understand and help resolve this, I’d like to ask a few quick questions:

• Please check again that are you using Work/School account (company tenant) or Personal Microsoft account (@outlook.com or @hotmail.com)?
• Did this issue start recently, or has it always been like this?
• Do other users also see your name as “Unknown user”, or is it only on your side?
• Are you unable to connect with all users, or only specific ones (for example, external users)?
• Are you trying to connect with users inside your organization (internal users) or outside your organization (external users)?
• Have you tried signing in on Teams web (browser) or another device, and does the same issue occur?
• If possible, could you also share a screenshot you see when trying to connect with others? Note: Please understand that as a forum moderator, my role is to provide general guidance and troubleshooting support. I don’t have access to internal systems or backend tools, and I appreciate your understanding of these limits.

I hope the information shared helps point you in the right direction. Thank you for your patience and understanding. I'm looking forward for your update.

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