So, I am very new to the hobby of lock picking and did not know the generally accepted "rule" of not picking locks in use (lesson already learned now, unfortunately). Anyway, I am sort of like an unofficial TA in this dance class I take at my local community college. One night before a performance the teacher was late and the latch had been fixed on the window we normally went through to open the room with the dance floor when we wanted to practice early etc. so I decided to try and pick the lock (stupid me). I was a little surprised that it actually worked, (and secretly delighted and a little terrified). At the end of the night when the teacher went to lock the door the key would only go halfway in...

So I went online and read that the pins could have fallen back down into the lock, so I went back and tried pushing the pins up and turning. It worked. The door was now locked. Fast-forward to the next night (performance two) my friend texts me and tells me the same problem is happening. At least at this point they don't have to worry about the door being unlocked, and they can open the other door and then open it from the back, but the lock is not working. Is there anything I can do to get it working again without taking it apart. I am assuming it is a master key system and something went wrong with one of the master key pins, but I can't really figure out what...