I deleted my Facebook account several months ago, I did not merely deactivate it, I did a full deletion. Then about one month ago I got a notification for a Fac

I deleted my Facebook account several months ago, I did not merely deactivate it, I did a full deletion. Then about one month ago I got a notification for a Facebook group. I wonder how that works? Either Facebook groups can somehow contact you based on an email address rather than an existing profile, or some other weird shenanigans are going on that reflect the account was never actually deleted and some bug somewhere managed to still get a notification to me.