NEW IPHONE 5S BROKE? HOW DO I FIX IT?

So I just got this thing for christmas from my mom and I havn't dropped the thing once but 5 months later these gray vertical lines came up across the screen like so kind of pixel malfunction or something… I don't know what to do because we don't want to pay for this because its not our fault but AT&T wants $200.

Added (1). I agree I hate iphones they suck but what do I do cause i'm stuck with it

This is what happened to my previous iphone 4s, it just appeared out of no where, that's why I switched to samsung because I think iphones are just a big rip off And breaks easily

Before time runs out, use your courtesy Applecare. Yes. Apple gives you 1 year free warranty on defects, errors, software problems, but not damage caused by you. Best thing to do is pop in the store and do the Genius Bar thing. Either they fix or replace or tell you 'no'. Only one way to find out. Best luck.