This occurred because the story variable that unlocks the door is not properly set. Did you interact with any Chapter 6 events by chance? If so, that is why the door was locked.
This save did not require conversion, but loaded inside of a desk, and not in the listed location for conversion. I have put you inside the League Administration, and savefile conversion prompted. You should be good to go.
Game.rxdata
Where are you at in the story? And have you tried changing your time via your system settings? If that doesn't work, they you may be on a story time lock.