During the Season of Arrivals I completed the Prophecy dungeon and was considering buying the hoodie, at the time I was able to access the code and redeem it. I went to buy it on 11/9 at 11pm cst and all it said was "System is currently disabled." The rewards tab is back online now and it says that I needed to complete the dungeon flawlessly. I don't know if had always been this way, or just changed when beyond light dropped.