Why does my camera freeze then blur when I switch it to rear?

My camera hasn't been working for over a year. It is starting to bother me because I cannot use the rear side of my camera. I have gone deeper into this problem and a lot of people have the same problem too. I went to apple a few weeks ago and they told me to reset. It did not change anything. I really want to get this fixed because I take a lot of photos and that's hard to do if your camera doesn't work. My camera freezes then turns blurry when I switch to rear. I want to solve this problem asap. Thank you.