Motion Sensor in my iPad Doesn't Work Anymore?

I dropped my iPad a few months ago, and it took a bit of damage around the edges but still worked just fine. Now, it's stuck in landscape mode no matter what I do. I use it for the most part of the day for writing and watching videos. I always keep it well charged, don't keep over 3 things open at once in the background, and avoid filling up all the memory on it. It is 16gbs and I have had it since Christmas. Is there any way to fix it?