Continuing the discussion from Contact_sync problem "That email already exists in the system. Please choose another email":
Has this issue been solved? How can I add/sync a contact when it already exists in the system without knowing its id?
Let’s say that someone subscribed to one of my lists in AC via external landing page and after some time decided to sign up an account in my app. I want to add him to “app users” list in AC from the level of my own API but I don’t know if he/she exists in AC and what his contact id is…
I need a method that simply add or update a contact no matter if the email address exists or not. I think this one https://:account.api-us1.com/api/3/contact/sync was supposed to work like that but it doesn’t.