Chosen Solution
A week ago i bought a replacement screen from ebay, installed it and it worked great on ios 11.4.1. today i updated my phone to ios 12 and the touchscreen doesnt respond anymore. is apple back again with the no touch on after market screens????
OK I managed to fix mine and force a working upgrade to IOS12 at the same time. I forced the device into DFU (Device Firmware Upgrade) mode - instructions on that are on the web depending on your model. Once that had completed I connected to iTunes and restored my latest backup and the upgrade to iOS 12. I now have a working phone again.
