Quote Originally Posted by Akira_Tenshi View Post
I am guessing you have not unlocked the achivement category and so can not earn seasonal event achivements.
Even if you have not unlocked the event achievement category, it is retroactive. If you earned the achievement before unlocking the event achievement category you will get it when you do finally unlock the category. In your log you will see all of them list at once according to whatever you earned.