Managing personal Outlook.com account settings, security, and privacy
Use the Microsoft sign-in helper first. It can identify the issue and may offer the option to talk to an agent: Sign-in helper
For direct support, go to Contact Microsoft Support, enter the problem, select Get Help, and if more help is needed, select Contact Support.
Important: support agents cannot send password reset links or access and change account details.
If the account may be compromised, use the recovery flow here: Start. That tool asks for the email address or phone number and either shows self-help steps or offers the chance to talk to an agent.
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