Use the following steps to view information related to sign-ins and secure your account.
1) Check your sign in activity on your account:
See when and where you've used your account (you should be able to locate if there has been someone else signing into your account here).
https://account.live.com/Activity?mkt=en-US&refd=account.microsoft.com&refp=security
2) Sign yourself out of all trusted devices:
https://account.live.com/proofs/
3) Turning two-step verification on or off for your Microsoft account
https://account.microsoft.com/security?lang=en-US
Add a new way such as Text a code or other options to stop the use of single factor authentication (password only).
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