Can't sign in on facebook on mobile - Facebook Apps

You must be able to receive text messages in order to sign up using a mobile number. If you are unable to receive text messages, or have trouble receiving one when you try to sign up with your mobile number, try registering using an email address instead. You can do this by clicking the "Register using your email" link on the sign up page on the mobile site, or by signing up on the computer.

If you are still experiencing issues, you can always try signing up on the full site by going to www.facebook.com
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