Airport card is not installed after replacing the screen

We recently purachsed 13" lcd screen from ifixit and replaced it sucessfully but the problem is we are not able to connect to wifi as it says airport card is not installed, but we double checked the connections everything is connected and fine, so we are wondering what would be the issuse another issue is when we shut down the laptop it restarts automatically so we have to hold down the power button it turn it off. is this a OS releated issue or will it be a hardware releated issue?