Camera flash disabled

I have an iPhone 5 running 9.0.2.

Sometime recently after an update I noticed the camera not working. I could it the camera switch button and the rear facing camera would work. I then hit the camera button again and noticed the warning button. Attached are the screen prints that show what I see. what do I need to do. Is it a hardware issue or is it software? I don't remember my phone falling or anything physically happening that would have damaged the flash. Any advice would be helpful.