Autofocus failure with AF.S lens

My auto focus problems with this same camera, happened when I replaced the focusing screen. The metal drop down tray that holds the screen, is very delicate, and now even the slightest bump of the camera (even in a camera bag) and the focusing screen moves, or drops out completely. If it moves slightly the camera will just not auto focus on anything. Your problem may be something else but Ive solved my problem by slightly bending the metal frame so it keeps the screen in place.

I also bought mine recently and I can’t change the focus point plus the camera autofocus is slightly off. I did try all basic troubleshooting problems but so far I cant find where the problem is. Did anyone experience a similar issue? Please don’t suggest unlocking the focus because it was the first thing I checked. So the focus point is stacked in the middle and I’m not able to select any other focus points.