Check in each of your email folders. Maybe you signed up for your Ankama account with an email address you don't often use and you haven't thought to check it.
Be sure also to check the Spam or Undesirable emails folder. Some email providers put automatic filters in place. Emails from Ankama might have been placed in this folder.
Still unable to find the email ?
If you still have access to your account, you can change your email by going to your account management interface. You'll then receive an email with a link to click in order to activate your new email address.
If you are unable to successfully change your email address from the account management interface, you can contact Support.