You don't need a password to stay logged into Facebook; you need a "session cookie." Modern hackers use malicious browser extensions or compromised Wi-Fi networks (Starbucks, airport) to steal your active session cookie. Once they have that cookie, they paste it into their browser and are instantly you—no password required.
Here is an essay on the topic of Facebook hacking, covering its methods, impacts, and how to stay safe. facebook hakar
: If you are locked out and your email doesn't work, go to the Identify Your Account You don't need a password to stay logged