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Hello. I created mesh items using blender. I always have this problem when I make items like a thin plane. For example, I made that using the blender, image1 But when i upload that in the game, it's not same image2 image3 It's okay on the blender like this, but In the game, the side of the object is invisible in all directions it's very trouble. Does anyone know about this problem? please Tell me how to fix it Thank you