I am not able to login to Teams app from Android phone

Disclaimer: This platform is in Korean. However, I noticed that your message was written in English, so I will respond in English to ensure clarity and provide better assistance. If you would like me to respond in Korean next time, please feel free to leave a reply in the comments below.

Dear @Sunny Kim,

Thank you for reaching out and I understand how frustrating it can be when you are unable to access Microsoft Teams on your Android device, and I sincerely apologize for the inconvenience caused.

To better help you, I need more information about the following content to systematically diagnose the problem.

1. What version of the Microsoft Teams application are you using on your mobile device? Have you checked for Teams updates? Version update history for Teams app deployments - Office release notes | Microsoft Learn 
2. Have you tried to log in to Microsoft Teams on any other device? If so, did you encounter the same error?
3. Are you able to sign in successfully using Teams Web or the desktop application? 
4. Are you able to log in to other Office mobile apps (e.g., Outlook, Word, Excel), or do they show similar errors? 
5. May I know what other troubleshooting steps you have tried so far? 
6. If possible, please take a screenshot of the issue you're experiencing so I can better assist you.

In the meantime, please try some steps below and check if it helps:

1.Restart the app

Go to Settings > Apps > Apps and find the app. On the App info page, tap force stop. Then, open the app to restart it.

2.Completely quit Teams, clear the cache (%appdata%\Microsoft\Teams\Cache), then restart. Clear the Teams client cache - Microsoft Teams | Microsoft Learn 

3.If possible, please use Microsoft Authenticator to verify the login and keep it in the background. Try to log in to other Microsoft applications: such as Teams, Outlook, OneDrive, etc.

4.Remove the account completely from Android: Try removing and re-adding your email account:

Go to settings > Accounts > Remove school/work account > Reboot phone > Reinstall Microsoft Teams > Sign in only after reinstall (don’t let Android auto-add the account)

5.Check app permissions

Ensure that Teams android has all necessary permissions:

• Go to Settings > Apps & notifications > Teams > Permissions.
• Make sure all relevant permissions are granted.

6.In addition, please review and apply the troubleshooting steps outlined in the referenced article to determine whether any of them address the issue in your environment. Troubleshoot notifications in Microsoft Teams mobile apps

7.Reinstall Teams. If the problem persists, try completely uninstalling and reinstalling it. 

• Uninstall first: Uninstall Microsoft Teams - Microsoft Support 
• Then reinstall: Download Microsoft Teams Desktop and Mobile Apps | Microsoft Teams

Please feel free to reply below if you have any update or further concern.  

Your understanding and co-operation are highly appreciated. Thank you for your precious time. Have a nice day!

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