Normally, you must have completed the
In the Tentacles of a Dangerous Plague quest and its sub-quests, or you must cancel completely.
But now that the event has ended (only the rewards shop is open), you unfortunately do not have the chance to complete this quest.
If you still have this quest, please cancel it. Try to talk with NPC's on browser. Also be sure to clear the caches.
If this problem still continues, I may suggest that you request assistance from
Support .
We are still looking for alternative solutions for this and will share them with you when we find. Thank you for your patience.