Have you tried connecting to iTunes using DFU mode? To do this, plug in the phone to your Pc/mac via usb. Then press and hold the volume down button as well as the power button as the phone boots. When the display turns on, let go of the power, and keep holding the volume down until it shows up in iTunes. You should get an error code to help diagnose it further or reset it.
Hmm. If it works for a few minutes then it is more likely to be a software issue rather than a hardware one. Have you tried a full factory reset, or going back to the last version of iOS? Does removing the SIM card and putting it back in help? If possible, could you try another SIM card for a few hours and see if there is any difference
Hi, It sounds like you have broken the LCD or digitiser behind the glass. If you can replace it yourself, then first check that the connection hasn’t came loose and that is why. If not then you may have to replace the whole screen. A tutorial is here Motorola Moto G4 Play Screen Replacement If not, there are many companies who will fix it for about £50 ish.
Hey, Have you tried a different display cables? If not then a different OS (run one off a usb). If not, then it could probably be a GPU problem, as if the ram is faulty/missing it will not show any image at all