Click the link in that email to confirm the addition of this email to your Facebook account.If the link in your email doesn’t work:Copy the confirmation code from your email.In the Contact section of your settings, click Confirm.Paste your code and click Okay.To change your email address, you’ll need to remove the old email address first …
https://www.justanswer.com/email/lqdv7-facebook-account-old-email-address-no-longer.html