Facebook is temporarily unavailable. We are working on it...?

[Vivian Darkbloom]

What does this mean? It's been 2 days since the first time this message appeared, and I still can't log in. My profile is still visible, and I can log in to other accounts, so what is the problem?
Who said they are mine?
@abraXus I'm not breaking any rule, as far as I know, but IF I actually did, and Facebook had locked my account, as you say it has done, would it still be visible by other users, as it is now? [Excuse me for my English, I am not a native speaker]
Actually, when I try to log in this comes out:
Review Recent Login
Someone recently tried to log in to your account from an unrecognized device or mobile device. Because you enabled login notifications, your account is temporarily locked. Please complete the following steps to regain access to your account.

(Facebook always asked me to name device. I did a couple of times but then stopped, because no matter what, it kept asking me to name a device every time I logged in)

So I follow the steps, and then the above message (Facebook is temporarily unavailable) appears.
Do you still believe this has to do with breaking FB rules or does it have to do with this 'uknown login' thing?

[abraXus]

"other accounts"?

well since it's against the rules to create more than one account, my guess is that facebook has discovered that you have broken the rules by creating more than one account, and has locked the account in question

if they arent yours, then that means you are breaking a different, much more serious rule (identity theft) - no wonder your accounts are getting locked

[Struan]

I had the same problem (not through logging onto other accounts I might add). It let me through the initial login but then told me I had been logged in from a different location and asks if this is ok or not, say no and it will let you to change your password and access will be granted.

Your situation may well be different however.