Some tips for keeping your Marriott account secure:
- Make sure your password does not appear on https://haveibeenpwned.com/Passwords. If it does, change it immediately.
- Make sure your password is complicated and unique. Ideally, it should be a randomly generated password (ie: https://1password.com/password-generator/)
- Make sure you are receiving email alerts from your account. That way, you can immediately address anything suspicious.
- Make sure all of your personal info on your account is up to date, including both your phone and email.
- Enable 2-factor authentication.
Of course, nothing is foolproof. Somebody can always call Marriott pretending to be you. But if you can keep your login information off the dark web, your chances of being hacked are much smaller.