All my saved chests and items are disappeared after come back to game again

[TimothyEM]

When I save the items, close the game, then open Minecraft again, and come back to the world again all the items are gone the name is "Air". Please fix this in version 1.12.2.

My saved items have disappeared it says "air" when you come back to the world again

[TimothyEM]

It's random air and name edited and can't use it's gone