Are you attached to the net? Haha, seriously however, are you?
Assuming you have the best login e-mail as well as password (and also you're linked to the internet) there's a couple of points that may be creating your troubles:
Can't Login Facebook
Are you getting an error message? If so, examine the Facebook help page for descriptions and fixes to well-known issues.
Make sure you don't have any extensions or antivirus programs running that are blocking Facebook.
Have you attempted removing the application's cache? Most likely to Setups > Applications > Facebook > Clear Cache. If this does not work you can try clearing information also and also as a last option uninstalling as well as re-installing the application totally.
Did you sign up with your phone number? Make certain you enter the country code also when logging in.
If the app is informing you to upgrade your email address, this is probably since your email server is identifying your Facebook e-mails as spam.
If you've recently enrolled in Facebook you may require to verify your account first. If you've recently transformed your password, ensure you're trying to visit with the new password and not the old one.
If you're logging in by means of a web browser, see to it you have cookies allowed and that facebook.com is contributed to your list of secure sites.
See to it you have one of the most recent variation of the Facebook app for Android.
