When I put my Samsung S6 inside the Gear VR headset, I get a black screen for 3 seconds, and then my phone ignores the headset. Factory resetting my phone to reinstall the initial software won't fix it. The headset works though, my phone still responds to it. It gets brighter, and the screen subtlety flashes from it before turning black with the "x" in the corner.
The headset even works on other phones, so I don't know what I'm expected to do, as no one else has this exact problem that I've seen.
Just a note for anyone insisting this is a hardware problem, it's not, I've had this problem a couple of years ago and deleting all oculus related apps and starting fresh fixed it. My phone when factory reset, still had an oculus app because of an update from Samsung trying to promote usage of Samsung VR. This is of course why resetting my phone didn't work.