Is it a new account registered from Bananatic? If you have an existing one from before, you cant use this one to do our quests.
If it's one you made from Bananatic, then it's possible you have browser or some sort of issue. It would be best to clear cookies and cache or use a brand new browser and launch the game anew.
Plse log Support Tickets (tab on left) for any future tech issues. :) We can provide more info.