When signing in or creating an account, you may see the message, "The email address you entered is already registered through another method." Why does this happen?

This error appears when you attempt to sign in or create an account using an email address that is already registered.

Your account is already registered via Apple, Google, or email. Please sign in using the appropriate method.

If the message says, "This email is already registered with another social account," please try signing in using a different social account than the one you attempted.