Why would you call and tell them the reason? The agents dont know . You know that you need ITIN and that’s what you tell them that I need true certified copy of passport. If they ask why, tell them for w7, if they ask why then tell them about ITIN. The caller agents dont know things like that. Book an appointment online on website and just go. Why would you want to call and book appointment that’s not how it works. They have clear instruction that book appointment online, and while you book there is a section what do you want the appointment for, and a drop down has options and you select w7 and true certified passport. Print the appointment confirmation and take that with you.