This is a guess, but it has happened to me as well in the context of the buggy journey and/or game failing to save. In your case, did you notice a journey that you had completed but now was not completed? It seems to me in my experience that if you’re in the process of completing a journey, e,g. Thrall taker, and it bugs out, the game won’t save from that point onward. You can be playing for hours, log out, log back in, and all stuff/things from that bugged point onward is gone. It seems like the game has a strange interaction with saving game files and bugged journeys or journey steps. But this is just a guess and may not be what you experienced.