I am in repair, the Samsung J7 2017, with a problem. Suddenly, after the update to Android 8, the sensor stopped working, it is the touchscreen of the phone, that is, the screen no longer responds to the touch of the phone. The problem is that, most likely, on this device, the display module has been changed to analog mode. It is also famous, but from China and the release of Android 8, it no longer works.
The startup charger on Android 8 is the fourth and it is not possible to return to Android 7 using standard methods. Therefore, we use the untranslated instruction: