Sometimes, when playing on Minecraft, the world would freeze, however, it wouldn't crash. This means that you would have to force-close Minecraft, and re-open it. Upon re-entering Mineraft, the world you were playing in would disappear. It would not be in the worlds tab. When accessing the files via file explorer (C;users, local, packages....minecraftWorlds), the world is still inside the minecraftWorld folder (refer to image). For some reason, minecraft doesn't recognise it as a world (refer to image), and the world cannot be played in. I read somewhere that logging out of xbox live fixes the problem, but i wasn't signed into xbox live at the time Minecraft froze. This happened to two of my worlds, as can be seen in the image.

N.B. I created the same ticket a couple of days ago, but it hasn't been replied to yet, so I created another one, since this is a serious bug. There are other tickets saying that their word deletes after crashing, but none of them show that the files are still in the minecraftWorld folder.