When you book with a Military rate you do need your DD214. They give you 48 hours to fax it in. I have never booked direct with them, we always use our TA. Do you have the name, and email address of the person who took your booking? Also there are only so many cabins the book at this rate, and it can change. They may not have any left at a Military discount rate.
That is one reason I prefer to use a TA. Ours asked us all the important question from the start, even on our first booking.