When a user clicks "Login", Auth0 executes a signup if the user selects an account they never signed up with

[dan.woda]

Hi @kevin16,

I understand you would like to block logins from an existing email, across all connection types (google, facebook, auth0 database, etc.).

We don’t have an existing feature to block logins from the same email in different connections, but you could potentially do it with an action.

See this thread: Validate and Block Social Login If User Email Address already exists and not verified