Facebook login problems are caused by many issues. It could be something wrong with your email address or password or even your computer or tab you are using. It actually depend on the problem but you can just simply try some basic fixes to recover your account.
Facebook Login Recover Fix :
Option 1: Reset your password and reactive from your email address. For Reset Your Password Click Here
Option 2: If you still don't couldn't reset your password you can send e report to Facebook to take care of your issue. Describe your matter with full details and You will need to show them screenshot and proof that you can't access to your account for fast recovery.Contact Facebook for password - Click Here
Option 3: In case you forget your email you can access to your account by your cellphone number. Just enter your phone number in the email address box.
These are the simplest way to recover from your problem . I hope this helps you if you still cannot access to your account please let us know via comments. We will try to help you.