Ghost of Tsushima has been updated to version 2.13 today by Sucker Punch. You can find out the complete patch notes from here.
According to the developers, this update resolves an issue with the bomb pack ammo in the multiplayer mode, Legends, of GOT. The patch should be available to download now and it is a minor update so you won’t need to download much. Get the details on the changes below, or see them on Twitter.