If you can't remember which email address you used to set up your account, begin by selecting "sign-in" in the menu bar. Input your email address and hit enter. On the next screen, you will see a link to "reset password" beneath your email address.
If you have an existing AIDT account, you will receive an email to the provided email address with a reset password link. The reset link will only be active for 48 hours. Use your email address and new password to sign into your account.
If you've tried the reset password link and didn't get an email within 10 minutes, try using an alternate or old email that you still have access to and follow the same steps as above. Once you access your account, change the email to your current email address.