Bastok Mission 2-3 Error

Platform: Windows 7, Windows 8 and Xbox 360
ISP:Comcast
Type of Internet Connection: DSL
Internet Connection Speed: 20mb/s
Date & Time: 2:15 pm EST
Frequency: Always
Character Name: Kelebros
Race: Galka
World: Asura
Main Job: Monk 40
Support Job: Warrior 20
Area and Coordinates: Balga's Dais
Party or Solo: Solo
NPC Name: None
Monster Name: None
Steps:
After defeating Warchief Vatgit I proceeded through The Emissary quest until I got to the fight with the Seeker and Dark Dragon. I died a few times before giving up and leaving.

Eventually I left my account dormant for a fairly long time but just restarted recently, looking to finish up most of the content before the 360 shutdown.

After leveling from 33 to 40 I went back to try again and now I cannot enter the battlefield. When I examine the pedestal I get told "A cursed seal has been placed upon this platform" and then nothing happens.

I cannot travel to the fight to finish this mission which has locked me out from doing any of the nation quests.

Have you checked to see if you need a new KI? Some battlefields consume the KI, so you may just have to go back to an NPC and get a new one.