Theme Missing

Dear @Yash Machhi (US), 

Thank you for posting your question in the Microsoft Q&A forum.  

The new Outlook is web-based, so please help me check how the modern themes currently display on your current web version and provide a screenshot. 

Please help me click on Settings > General > About Outlook > and take a screenshot of the version you are currently using. 

Please try logging in on a different device (another laptop) to see if it displays normally. 

I see you tagged it as 'for business,' is this a work account? If so, do your colleagues see the modern themes displayed normally? 

Please help me perform an online repair according to these instructions Repair an Office application - Microsoft Support. 

Please help me uninstall and reinstall the app. 

If the issue persists, please help me create a new Windows profile, download the new Outlook on the new Windows profile, and check if the same issue occurs Manage User Accounts in Windows - Microsoft Support. 

Please help me answer all the questions above fully and provide the results of the three steps (online repair, uninstall - reinstall and create new Windows profile). From there, I will be able to determine if the error is due to your account, the app, or your device. 

Looking forward to your response! 

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

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• To change the theme, navigate to the Appearance settings within the application.
• Under the Dark mode section, select from 'Light', 'Dark', or 'Use system settings'.
• In the Themes section below that, different color options are available to choose from.