So first, automatic account linking is a dangerous from a security point of view (happy to explain why if you want). But if you still want to do it, then you have a few options: - If the same email is used to sign up with google, and then they use email / password sign up, you could show an error to the user saying that they had already used this email to sign up via google and to use that (this is what we do on our site) - If you want to link accounts, you would need to maintain a separate table on your end that maps supertokens' userIds to your userId (many supertokens' IDs can map to the same, your userId). Then you would need to insert into this table based on the users email (post sign up), and also override all the thirdpartyemailpassword recipe functions to use your mapping when returning the userId. You can do both of these by using the override feature we have. It may be a little complicated to figure it out, but I can provide examples of how to do what you want.