Using Outlook for iOS in business environments for email and scheduling
Here's the relevant article.
Help with the Microsoft account recovery form https://support.microsoft.com/en-us/account-billing/help-with-the-microsoft-account-recovery-form-b19c02d1-a782-dee6-93c3-dc8113b20c42
Try the form but the rate of successful account recovery isn't very high.
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