Welcome breejesh patel,
Thank you for reaching out to Microsoft Q&A forum.
I'd like to gather a bit more information before suggesting additional troubleshooting steps.
- Are you signing into the Office app with a personal Microsoft account (such as Outlook.com, Hotmail.com, Live.com) or a work/school account provided by an organization?
- What is the exact error message or error code that appears after you enter your Windows Hello PIN?
- Which Office app is affected (Word, Excel, Outlook, or all Office apps)?
- Does the same account sign in successfully in a web browser?
In the meantime, please try this quick test:
- Open Settings > Accounts > Email & accounts
- Under Accounts used by other apps, select the affected account and choose Remove (if present).
- Restart the PC.
- Open the Office app and try signing in again.
Looking forward to your update.