iOS Facebook: "Error Signing In", fix - AppleToolBox
Having trouble signing into Facebook? Getting error messages like account unavailable or sorry, something went wrong? Learn what to do
13 Mar 2019 ... 1.1 Can't log into FB Messenger, Facebook, Instagram, or WhatsApp? ... 6 First Line of Defense with Facebook: Error Signing In ... Additionally, your connection to FB's Servers may be prevented by a firewall or other security ...