Hi all! We have a partner company that takes care of our integrations, but they are not too familiar with NS. We have Boomi integration that imports expense reports to our system. It has worked earlier just fine, but after changes to integration in our sandbox we now get error

<platformCore:message>Nonexistent externalId XXXXX for customer</platformCore:message>

when we try to add project to expense line. Has this happened to you, can anyone give a hint what could be wrong? The project is active and ok and it can be selected to that expense report & user in UI.