If you want to lock your iPhone camera in order to fix camera flashing iphone issue then you must follow the steps that are given below:-

1. The first step is to open settings on your iPhone.

2. Then tap on camera inside Settings menu.

3. Now tap on the record video option.

4. Then finally you have to turn on the lock camera option or you can set the recording resolution to ‘1080p at 60FPS’ for better video quality.