Old world missing from in-game list but visible in launcher

My old worlds disappeared from in-game list, but they’re still visible in the launcher, I can see the name, the last time I played, the gamemode, etc and I checked all the folders where the worlds might be stored, but I didn’t find anything and I didn’t delete the world, the last thing I remember I did was when I finished playing I simply saved the world, I waited until it finished saving and I left the game, and 1 year later when I tried to open it again my world disappeared inside the game.