Is it the red and the blue room puzzle? If u have matched everything, you can go back to the door and it will lead you to the right path.
It will also ask for 1 more action afterwords, but in case you are like other people who haven't found the red and the blue room (and perhaps the save room's bathroom), it would be at the hallway in the center. At left and right ^^ the bathroom should be by the left side of the save room. hope this helps!
Here is a quick image I edited by screenshots. Sorry if these rooms are hidden. It will be fixed next version
