In recent times, many people have been hacked on Facebook by bad guys, who will lie victim’s relatives/friends to take money/property from them. Unlike the previous Yahoo trick, with Facebook, once a password and account has been compromised, the bad guys will know a lot about the owner of the account as well as their friends and relatives. profile as well as the images and status that the owner of the account shares.
To enable this two-layer security feature, follow these steps:
First, you go to the Settings on your personal page.
Next, go to Mobile and click on “Add phone” to add your phone number. If you already have a phone number then press the “Confirm phone number” button to confirm the phone number you have provided.
Read more here:How to protect against scam on Facebook? - How to get

To enable this two-layer security feature, follow these steps:
First, you go to the Settings on your personal page.
Next, go to Mobile and click on “Add phone” to add your phone number. If you already have a phone number then press the “Confirm phone number” button to confirm the phone number you have provided.
Read more here:How to protect against scam on Facebook? - How to get