Hello, thank you for reaching out to Microsoft Q&A.
What is the exact error message you receive when you sign in with your @hotmail.ca account here?
https://account.microsoft.com/
Did the hacker replace your Username (Email address), and did you get 'This username doesn't exist' during the sign-in?
(OR) Did the hacker change your password or alternate security contact methods?
Have you already tried the Microsoft self-help article here to recover your account?
How to recover a hacked or compromised Microsoft account
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Microsoft always recommends that users secure their accounts by having a strong password and enabling two-factor authentication. So, even if someone knows your password, they won't be able to get into your account with the second factor of authentication, such as Authenticator or recovery phone number/ email address code.
How to help keep your Microsoft account secure