Thank you for your help, and yes i am using DiscourseConnect which is probably why this isn’t working. I think this is the approach I will end up having to do. Either that or I have to make a second call that SSO logins the user with the external id so that it is linked to their email.
Edit: I think the updateUser will also have the same issue as i do not have a defined provider, so probably the SSO login is my best bet.