A bug in an account verification system used by Facebook resulted in a wave of account suspensions Tuesday that had users locked out of the world s largest social network. Facebook discovered a bug in a system designed to detect and disable fake accounts, said Simon Axten, a Privacy and Public Policy Associate at Facebook. The bug caused what the company described as a very small percentage of Facebook accounts to be mistakenly disabled Facebook has since fixed the bug and as of Tuesday, the company was in the process of reactivating and notifying the people who were affected by it.
Source: https://threatpost.com/facebook-glitch-locks-out-accounts-111710/74680/