To stop your iPhone camera from auto focusing, you can try several solutions. One solution is to lock the focus on a particular subject by tapping and holding on the subject until you see a yellow box appear. This will lock the focus on that subject, preventing the camera from refocusing. Another solution is to switch to single-shot autofocus mode when taking photos of stationary objects. This will lock onto the subject and prevent the camera from continuously refocusing. Additionally, you can try removing or replacing your iPhone case, as some cases may interfere with the camera's ability to focus properly.