got this answear from mod Daiske :

There was problem with new event and after maintenance those problems were fixed. All new events were rested. It is not a bug.

However, if you spend your charms or refines before maintenance, please contact us via this email : narutoen_support@oasgames.com. We need your log file (you can save it by typing "hylogfile" while you are in the game and you are on the event page, windows that will allow you to save your log file will pop up). Please attach your log file to your email and also do not forget to add your character name, server number, UID and small description of the problem.