Starting a Minecraft World

You are trying to start a game while the "Online Game" option is checked. Uncheck this option, located right above the Start Game button, to begin playing the game offline.

In Minecraft, the world is saved to the account that is "Player 1" and starts the game first.

When the second player joins that world, he is saved together with the world in Player 1's save slot.

If the second player starts the game themselves, they start a new game with a new world and empty inventory, as they have no access to Player 1's savegame. To prevent that, make sure that Player 1 starts Minecraft and enters their world, and that Player
2 then joins that session.

If you want the two players to be able to play independently on the same world, you would need to rent (and pay for) a Realm that is hosted on Minecraft's online service.

Thanks, if you try creating a new world. Something similar happens once you re-open Minecraft or is this happening only with this specific world?

And, do you know if Minecraft received an update recently before this problem with your world started to happen?

Turn on xbox start minecraft go to download world and you should find the worlds you saved on windows 10

if there are any corrupted minecraft world im sorry but you got to start again.