I deleted my account there 10 years ago, about a year ago I needed an account to join a memorial group for someone. Facebook somehow knew that the email address I used to sign up with, which was new, was related to my old email address and tried to link my new account to my old data which was still there.

It also still knew a heck of a lot about me including suggestions for people I had just recently met. And some of them I only met once, in passing, never exchanged info with, and never saw again.