Writing Test

I was supposed to translate, "this year, on the 24th of December, I am going to cook Christmas Eve Dinner." I translated the latter part of that sentence to "je cuisinerai le repas du Réveillon," which was not accepted. The correct answer was "je vais cuisiner le repas...". However, there was nothing in the quiz so far to indicate that this was to be done in the near future. Was my answer technically correct, or am I missing something?
Thank you