I beat the game and completed the first three levels on heroic and iron. I came back a day later and now have up to the 7th level beat and no heroic or iron. I don't know if it's happened to anyone else. It's a little upsetting to have to do those levels over.
I haven't come across another user that experienced this problem yet, so I will forward it to an admin for you. Please wait for a response from them, ok? =)
