When Im in a mission, black screen.

[Battle_Beast_]

PLS help me :

    When I played mission over 30 mins or 1 hour or longer, it may turns black screen. The worst thing is that you can't see anything, and you  can't end the mission. All rewards gone. I have to Alt+F4 to shut down the game and restart. It happens almost every week. I tried to update my graphics card drive. But couple of weeks, again. what should I do?