Hi,
I have the same issue with the proximity sensor. I’ve found a workaround on the net (FP2 does not seem to be the only one with proximity sensor trouble). I pushed a small piece of aluminium foil on the sensor (see picture below). It makes the sensor feel that there is always light and the screen never turns off.
I will see with time if the workaround is not worst than the problem: the screen is on during calls so the cheek can interact with the screen.
