If you start game without turn on gamepad its not working. I have to close the game and open it again.
well, this seems to solve the problem then? a lot of games show the same behavior for me: controller is only recognized if turned on before launching the game.
aside from the things suggested here: PS4 controller will not work at all - #4 by Chemile0n
another thing might be to try with fullscreen vs windowed mode, and making sure not to tab out on 2nd screen while the game launches.