iPhone 5c charger works in wall but not in computers?

My second charger did work in my computer and then one day just would not. It still worked in the wall perfectly fine. I wanted to sync it though so I went ahead and bought a new one. It worked in my computer fine until yesterday I was charging it on a computer and it just randomly stopped. I know it's not my computer because it doesn't work on any computer. The charger still works in the wall but it's really frustrating that I can't sync my new music :/