Hello guys I recently tried to open my 3ds back case. The back case opened then the battery, but I noticed only 2 screws came out and 5 other screws wouldn't. I was also missing 2 screws! I sent it to Nintendo before, but I didn't think this would happen. Is there some technique to unscrew these screws? Whenever I try to unscrew them they will just not unscrew (sorry for not being to specific).