So I was doing the monthly quest in master difficulty when i ran out of energy and accidentally hit use Master key...instead of my energy refill..which is weird that option never shows up, now I can't enter master mode after completing heroic 100%. I ran the last chapter of act 3 (heroic) to see if i would get the key but nope, now I'm locked out..

So what am I supposed to do now? I spent units on the energy refill deal just to finish this asap.