Hi, I'm John! I will help you with this.
If you haven't tried anything yet please start by running a full antivirus scan on your computer using Windows Security and any third-party antivirus software you have.
To be safe, I recommend the following steps:
Check your account rules and forwarding settings, hackers create rules that automatically forward or delete emails. You can do this in Outlook settings under Mail > Rules and Forwarding. https://support.microsoft.com/office/manage-email-messages-by-using-rules-in-outlook-c24f5dea-9465-4df4-ad17-a50704d66c59
Just to be safe, I’d recommend to sign out everywhere. Visit: https://account.live.com/proofs/manage/additional Scroll down to Sign me out and select "Sign me out".
And changing your password again and enabling two-step verification if you haven’t already. This will add an extra layer of security to prevent future unauthorized access.
If you notice anything unusual in your account settings or purchase history, you might also want to check the Microsoft account security page https://account.microsoft.com/security to review recent activity.
"How to help keep your Microsoft account secure" https://support.microsoft.com/account-billing/how-to-help-keep-your-microsoft-account-secure-628538c2-7006-33bb-5ef4-c917657362b9
I really hope this information is helpful! Let me know if you have any further questions or concerns.
Regards,
John J.D.