Does the game end at 0.3 if you start the game from beginning. Otherwise, it sounds like you saved at wrong spot.
If you saved anywhere before you open the door, you should be able to play 0.4. If saved after you open the door (i.e. Black fade screen and credit screen), try using Back and see if you can go back to that choice or use any save that's saved near that point. If you don't have any, play the game from start.