I'd like to bring this thread back as I appear to be having a similar issue now. Does AF/KLM/Flyingblue delete accounts? I have logged in plenty of times this year when looking at a potential booking, but it has been about 2 years since I flew either airline or had any FB activity. I too would credit to Delta.

I need to make a booking via FB now and when I go to log in it tells me that they do not have my email address on file. I don't have any emails from them saying/warning of anything - the last was a marketing email in late February.

Really annoying and I'd like to avoid making a new account if possible since my current one is linked to my MR/UR accounts.