Why won't my phone connect to iTunes after replacing the screen?

Okay, so I had someone replace the screen on my iPhone 6s. In the process of replacing the screen, he disabled it. So when I went to plug it into iTunes to unlock it, I plugged it in and it pops up immediately after plugging it in saying "iTunes could not connect to this phone. An unknown error occurred" so I tried updating iTunes, updating my computer, restarting both my phone and the computer and it still will not connect and is disabled... help!