Solution 1: Check Either Facebook Server is down
There may be some server problem on the Facebook site and it might be for all. So, check either the Facebook server is down for all or it’s just you who is unable to access the login page.
Solution 2: Ensure to Enter correct login credentials
Make sure to enter your login credentials carefully. You can check your username and password details again that you have entered on the Facebook login page. If you can’t see your password then click on the show password link to see the password detail. Now, you can check whether it is correct or not.