Every month or so I'll get a handful of emails from Facebook saying it looks like I'm trying to log in and asks if I need help with that. Either they're trying to get me to re-join in a very pathetic way, or someone else is trying to sign up using my email address, causing Facebook to think they want to re-activate my account.
In my opinion, the messages are fraudulent about their intentions. They misrepresent a 'security-related' incident to get me to go on the site again.
Are you sure your internet profile elsewhere is not subjecting you to doxxing attempts? I know friends who are in publishing or blogging etc. with fairly well known profiles on the internet, and they seem to be targeted far more regularly with attempted unauthorised logins to their email and social media accounts.
I was contacted by an undergraduate asking for grad school advice. Five minutes later there were several emails in the inbox from Facebook with exactly that content. I don't normally receive anything at that address (everyone I know emails me at a different address). How do you expect me to give you advice when you pull this shit on me?
I'm not sure that what they are doing is even legal. Just another reason to NEVER use the same email/password combination on multiple sites. I wouldn't be surprised if other apps are doing the same thing.