Had the same issue yesterday and still getting the 1 minute message today. I agree creating a new character shouldn't be the solution to this. Locking the ability to progress via quests behind the campaign doesn't work if the campaign's are tied to buggy instances.
I had the exact same issue. Today I still have the "must wait 1 minute before entering" message. NCSoft really needs to review these issues and provide some answers as you can't progress. Really frustrating.