A workaround for using Quiet in certain missions is available until patch is released.
While the launch of Metal Gear Solid 5: The Phantom Pain is largely being hailed as a success, there have been a couple of glitches that have marred the game’s release a bit. Konami has said that it is already working on what is a potential game corrupting save bug and that a fix should be incoming in relative short order. This particular bug pops up when using the silent sniper Quiet as a buddy for missions 29 and 42 in the main story missions.
The company says that hits particular bug only pops up when using Quiet in a very specific way and because of this there is a workaround. Konami posted the workaround on the official website saying, “The bug is triggered only under certain circumstances in Episode 29 or Episode 42 when Quiet is used as your buddy. However, you may still safely use Quiet in these missions if you use the Butterfly Emblem throughout the mission or avoid raising your Bond Level with Quiet to MAX during the course of the mission.”
While this makes the game playable before a patch is issued, there are obviously going to be a number of people who point out that they shouldn’t have to do certain things in order to avoid the game glitching out. This bug is apparently affecting the game on every platform but Konami does want to assure people that it is working on a more permanent patch fix for Metal Gear Solid 5: The Phantom Pain.