Disappointed from USCIS

I received a notice from USCIS that my interview for citizenship will be on December 7. We will be in FL that time for another week of vacation. We went to Tukwila just to ask adjustment for my interview but the immigration officer just told us to go home and send a reason why I can't keep the appointment that they scheduled for em. Brian was disappointed and wanted to send complaint to our Congressman what the USCIS behavior. We were driving for more than an hour, burned gas and wasting our time ....and that is what their response. I just wished they will consider for those people that come to their office...and they will accomodate it.
Yes we have one main reason why we wanted to change it but then there is another reason why we wanted it early. Because we will be moving to Japan and I need to get a business passport so we are allowed to stay there for 3 years in Japan without worrying to get out in the country. Brian was told that he will be detached this mid of January.... We are waiting from the shipyard to tell us when we can get a business passports for the kids and me (waiting for the citizenship interview). Oh well......... What we gonna do?
Brian and I planned to send out letter tomorrow for requesting early interview but if ever they will give me a schedule late December then I will keep my appointment.. so then Mary and I will go home early Thursday and then attend my interview the next day. I feel that my a week vacation is not complete.