Managing personal Outlook.com account settings, security, and privacy
Hi Riddhi Salian,
You can change the birth date by signing in to your Microsoft account profile and selecting Edit profile info:
Change a birth date on a Microsoft account
The steps may differ if the account is currently classified as a child account or requires parental consent. If you cannot edit the birth date, please let me know what message or option you see on the profile page so we can guide you accordingly.
Thank you so much for your understanding.
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