Some popup prompt boxes do not appear after screen replacement.
I replaced the stop-working screen (the old screen did not shatter but just could not display anything but some vertical and horizontal lines) on my iPad Air 2 WiFi and Cellular using the screen replacement kit bought from iFixit.
After the replacement, the new screen worked fine except that I did not migrate the magnetic sensor correctly (guess my soldering skill was not good enough) so the iPad could not go to sleep with the case lid closed or when I pressed the sleep/power button on the top but I guessed I could live with that.
Then after a few days of use, I noticed there was something more appearing to be wrong. That was some pop up prompt boxes (not all) would not show up. For example, I installed an app which needed to access the camera and photos from the iPad, usually for the first time, it would pop up a prompt box asking for permissions to the camera or photos, but that prompt could not show up on my screen and as a result, that app could not access the camera or photos. However, the built-in camera app itself worked just fine and I could take photos using both front and back cameras. I have also noticed that even from the Messages app I could not access camera or photos . Another example was the 2 step verification code, if I tried to log in my Apple account from a new browser on a PC, after I entered my password, it would send verification code to all of my other Apple devices including this iPad, I could even hear the prompt sound on my iPad but the verification code prompt just did not show up on the screen.
I have tried a lot of things including resetting the iPad, reinstalling the iOS in recovery mode from iTunes on a PC, or even upgrading it to the iOS 11 beta version. I have also checked a lot of settings including the restriction, I am sure I did not enable the restriction at all. But none of the tries has ever fixed this issue. And in the privacy setting, nothing was showing up under camera or photos which I did not have the chance to enable or disable any apps access from there.
What could be wrong with the screen replacement which could lead to this problem? Pleas help, thank you very much.