I'm using Flutter and Firebase.
I allow new users to sign up using Email and Password, and also Apple and Google sign in.
Now I need to prevent the same user from creating an account with Email and Password, and a different account with Apple/Google sign in. As it is currently, they can create two accounts, and I see two different accounts in the Firebase console. Is there a way to make sure that once a user signed up with one method, he cannot sign up with another method? For example, check if that email already has a user associated with it?
Thanks