Replaced my cracked iPad screen twice, still it won't work. Any ideas?

I dropped my AT&T iPad Air 16GB and cracked the glass and damaged the digitizer enough to where it wouldn't respond to any touch gestures. The LCD screen still comes on and works properly. I went ahead a did the replacement and everything went smoothly but the new digitizer still would not respond to my touch so I blamed it on a faulty digitizer and returned it and ordered another that was a bit more expensive from a more reputable vendor. And once again the replacement went smoothly but when I tested it, the digitizer would not respond to any touch gestures. The home button on both replacements worked just fine. So I am not too sure what the problem is. The connectors inside the iPad are fine and there doesn't seem to be any damage that I can see. Anyone else encountered this before?