It happened to me all the time. Save game with F5 functionality. And try to reload with F9. If it doesn’t help then you will need to ‘win’ the mission. I’m still not aware if it is permanent corruption of mission part in campaign or just a casual case. I don’t have time to test it. My config is with GTX 1060.
Unfortunately it’s not as easy as reloading or capturing a bug report - all programs close when this happens, and I’m left with a PC that’s still “on” but doesn’t even detect the monitor. The only thing I can do is reboot the PC.