Hello @Srikanth Bhat,
Thank you for your post.
I'd be happy to help, but I would need a bit more information to better understand the issue before suggesting the next steps.
Could you please let me know what specific error or behavior you are encountering? If possible, please share a screenshot of the error message or the page where the issue occurs. A screenshot would help me determine whether this is related to Excel, licensing, authentication, or the NGO portal itself.
To better understand your Microsoft 365 environment, could you also check which license is assigned to your account?
Please sign in to: https://portal.office.com/account/?ref=Harmony
Once signed in, navigate to the "Subscription" section and take a screenshot showing the full license information assigned to your account, similar to the picture below. (If any personal information is displayed, you may mask it before sharing)

In the meantime, could you also let me know whether you're able to use Excel on the web? You can test this by signing in to: Excel for the Web - Microsoft 365
and confirming whether Excel opens and functions normally there.
At the moment, I don't yet have enough information to determine whether the issue is related to the NGO portal, Excel, licensing, or account authentication. Once I have the screenshots and the additional details above, I'll be in a much better position to guide you toward the appropriate solution.
Thank you for your cooperation, and I look forward to your update.
Best regards,
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