I am having an issue with Journey Builder Entry Source. I want to use my synchronized Sales Cloud data as the entry source. When I choose Lead as my Entry Source - no problem, the lead is there and I can choose Lead ID (Lead):
But when I want to do the same for Contact, the Contact ID (Contact) is not there:
The data model was inherited from Sales Cloud and looks fine. Any idea why I can't choose a Contact for my entry source?