Second, I have updated stuff on IAFD tons of times, and they always get back to me AND update the info (except once when I was wrong - oops!).
How are you sending it to them? What I do is when I'm on a star's page, I click on the "Submit bio corrections" button. Then I type in what the correction should be, and provide a link to where I found the info (including telling them where on the linked page they should look, if it's a page with lots of stuff on it). Then I provide my email address and I make sure that the tabs "Send Confirmation EMail" and "Send EMail When Issue is Resolved" are both checked. Then I type in the characters shown for verification purposes as it says to do. I always get the confirmation email almost immediately, and then depending on how busy they are, I'll get the email about the issue being resolved between one day and one week later.
If you do exactly the same as I do, I imagine you'll have the same success as I have. Good luck!
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