Thank you for posting your question in the Microsoft Q&A forum.
Based on your inquiry, we are very sorry to hear that your account has received an amount of malicious sign-in in activities. In my perspective, I suggest you following these steps to secure your account:
If you use your personal account:
- Sign in https://mysignins.microsoft.com/
- Choose Security Info -> then choose Sign out everywhere
- Change your password
These steps will assist you sign out your account from all devices
For more secure, you can remove and re-register your MFA on your devices
If you know your admin in your organization:
- Sign in Entra ID
- User -> All Users -> Your Account
- Revoke Sessions (requiring the user to re-sign in from all devices) -> Reset password.
You can also ask your administrator to reset your MFA to help secure your account. Please share this article with them and request that they follow the steps to reset your 2FA, so you can re-register it on your devices
If you need further assistance, please let us know.
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