What do you mean the scene turned 2D? If you are referring to the fact your scene camera is in Isometric mode, rather than perspective mode, simply click on "Iso" under the 3D gizmo in the top-right corner of the scene.
This is surely a scaling problem, one of the scales of the things game object or it’s children is set to 0, try to find it and then set it to 1
What do you mean the scene turned 2D? If you are referring to the fact your scene camera is in Isometric mode, rather than perspective mode, simply click on "Iso" under the 3D gizmo in the top-right corner of the scene.
– Hellium