I got an email saying I requested a new Facebook password but I didn't make this request.
If you received a Facebook password reset email that you didn't request, it's likely that someone accidentally entered your email or username when attempting to log into their account. This often happens if you have a popular username or email. As long as you don't click the link to reset your password, no action will be taken and your account will remain secure.
If you think someone is entering your username by mistake, you can turn off password resets for your username. To do this, click the let us know link in your email and follow the onscreen instructions.
If you receive a second email saying that your password was reset, you should immediately secure your account.