Chosen Solution
Ok so sometimes when my phone is locked (black screen) and i want to unlock it by pressing and holding home button it wont do anything. What i found to be working is pressing once power button - screen lights up. And than home button work like intended. Same when some one is calling me. The phone will ring but the screen is black - like locked. To answer the call i have to press power button once. Than i can see the caller on screen and answer. It only happens once a day. I tried restarting and restoring phone but it doesn’t work. Also tried disabling touch id.
The home button flex cable may be going bad. Try to replace the home button itself and see if that fixes it :)