How to fix "Failed to open map file. This is most likely because the map was saved with a newer version of the engine."?

At night after I finished, I save the level like usual.
and in the morning, when I open my level again. and suddenly it says

“Failed to open map file. This is most likely because the map was saved with a newer version of the engine.”

and I can still open the map but there is nothing

but the other map is ok

I’m using ue 5.3.2

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