camera control

So I've been playing LOL for a good month and when I started I used the arrow keys to move around my camera to where my player is and obviously I got used to it and then just now as I was playing a game my arrow keys stopped working? Like I can't move around using my arrow keys anymore I have no idea what I have done I tried looking at the options menu and changing the hotkeys but I'm just confused I can't seem to get it back to normal, So how do I change my camera moving thing back to my arrow keys???