Managing personal Outlook.com account settings, security, and privacy
Hey there! Nice to meet you!
Since you were able to request a security info change, I'm afraid your only option is to wait for the 30-day restriction state to complete. The hacker has their email added to your account, this means that they have full control over your account, and they can simply cancel your security info change request.
If this happens, you will need to try requesting again, and hopefully, the hacker will not notice.
Unfortunately, it is also not possible to bypass the 30-day restriction state.
However, if the 30-day restriction state is complete, you will be able to remove the hacker's security info email/phone number from your account using your newly added security info.
Lastly, please be advised that Microsoft Support will not be able to assist you with manual recovery, unblock, security info management, and escalation for this case, as stated in this article, that they are not permitted to send password resets, access, or even change any details on the account:
Thank you for your understanding! Please let me know if you need anything else.
Best regards,
Darhyl