New Screen wont work, any ideas?

So I have a bit of a problem, I purchased a new screen for my cracked ipod touch, when I replaced it, the new screen wouldn't work, so to see if the new screen was faulty I checked it with another ipod touch and it worked fine. I put the old cracked screen back in the original ipod and that had no problem working. So now I cant figure out what the problem is, the new screen obviously isn't faulty because it works on the second ipod, and the original ipod works as it's own original cracked screen still works on it. Any ideas?