Im creating a transactional journey that is passing along an ID, which is related to a contact (field on Contact object in Salesforce) and which im pulling into Marketing Cloud. Im currently using ampscript to retrieve first name, last name, etc from the contact table using this ID, however when testing the journey, its giving me the "required email address not found" error, as the API connected to the journey is not passing along an email address. Is it possible to lookup the email address from the ID the API is sending? I think I could create an automation to populate a new data extension, but this defeats the purpose of a transactional fed journey, as I dont want to wait every hour for the emails to send.
Thanks!