Chosen Solution
Hello! I am working on an iPhone SE which has a randomly unresponsive screen. The display had a small crack from the upper edge to the earpiece, so I assumed the display unit would be damaged. However, after I replaced the display unit with digitizer (not the camera + sensor module and the metal shield), the display still behaves the same way. Any ideas what the issue is? It behaves almost like a loose contact.
It can be a issue with your Touch/Digitizer IC, a replacement will fix the issue.