Are you connected to the internet? Haha, seriously however, are you?
Presuming you have the best login e-mail and also password (as well as you're attached to the web) there's a few things that could be triggering your troubles:
Facebook Login Problems
Are you getting an error message? If so, inspect the Facebook help page for descriptions and also fixes to recognized problems.
Ensure you don't have any type of expansions or antivirus programs running that are obstructing Facebook.
Have you attempted clearing the app's cache? Go to Setups > Apps > Facebook > Clear Cache. If this does not function you can attempt clearing data too and also as a last option uninstalling and also re-installing the application entirely.
Did you register with your telephone number? Make sure you type in the nation code also when visiting.
If the app is telling you to upgrade your email address, this is probably because your e-mail web server is labeling your Facebook e-mails as spam.
If you've recently enrolled in Facebook you might need to verify your account first. If you've lately changed your password, see to it you're trying to visit with the new password and not the old one.
If you're visiting by means of a browser, see to it you have cookies made it possible for which facebook.com is included in your list of risk-free sites.
Make certain you have the most recent variation of the Facebook app for Android.