Steps to Enable Login Notification
1. Open you Facebook Account and go to Settings.
2. After settings got open navigate to Security tab and click on it.
3. Then you will be able to see login notifications over there, click on it.
4. You will be allowed to mark Email or Text message/Push notification.
5. Mark as per your requirement, whether you want to receive notification whenever your account is accessed from a computer or mobile device that you haven’t used before. Suppose if you mark Email then you will receive notification in your Email account inbox and suppose if you mark Push notification you will receive notification on cell phone via SMS.
6. If you want to receive notification through Email just mark Email and save the changes or if you want to receive notification on the cell then mark Push notification and it will ask you to add your phone number to your timeline.
7. Register your phone number to Facebook Account and click on save changes.