Did you accidentally change the length of your wall? Did you delete an object by accident?
You can always undo what you have done in a room just by tapping the "Undo" option (located in the top right corner of the screen), as long as you don't exit the room or level you've been working on. When you are editing your project, every time you exit a room or a floor, all your changes and adjustments are being automatically saved. Therefore, always be careful before exiting your room.
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