How to prompt to join the account when signing up via the same email of the existing facebook account?

Hi experts,
I am very new to Auth0, and right now I am maintaining an existing project with auth0 already setup.

Currently, it has an issue as the below reproduce steps:

  1. User sign up with facebook with email addr: user@example.com
  2. User sign up with email with the same his email’s from facebook
    Our system ends up with 2 separated accounts.
    The expected behaviour should be: prompt that there is an existing user, and do you want to join?

I don’t know where the logic exists, could anyone give me some hints? Thanks

Regards,
Ron

Hey there @ron.liu!

The behaviour is totally correct. To describe you how it works. As you said if you have a user with email adress: xyz@mail.com and he signs up using login (email) + password and then using this same email in any other connection whether it’s Linkedin, Facebook whatever, it will be treated as separate users.

To make it work as one user you should use our account linking feature that is described step by step here:

Have you had a chance to check the docs I provided above?