If you are seeing this message “Facebook will be back soon” when you try to login. You do not need to worry because few hours ago, Facebook Server went down due to database maintenance and improvement. If you are watching this screen in your browser, then dont both facebook acount recovery.
This is an official announcement in which a link is given as READ MORE. You might see this screen too:
A message showing to those affected suggests the problem is part of scheduled maintenance, though Facebook’s own developer page makes no reference to those issues.
“Facebook will be back soon,” the message showing to users reads.
“Facebook is down for required maintenance right now, but you should be able to get back on within a few minutes. In the meantime, read more about why you’re seeing this message. Thanks for your patience as we improve the site.” This link screenshot is given below which ensures that your account will be safe.