My world just disappeared...

Hello! Let me begin by saying I love this game and consider it one of my favourites, although I do find issues with it I yet would continue playing since it brings unlimited creativity. This is a recent issue that I've encountered, I suppose it's rare, but it happened. Somehow my world disappeared when I decided to save and quit while I was in The End. The folder is still there, I've tried backups but it won't appear on My Worlds. Please fix this! It's a big worry to have a bug like this that would make your world's disappear