[UE4-27] Help BSP disappears Multi-User Editing

Hello we have a bug with a friend when I modify a someone BSP on our maps my friend sees it disappear and it’s the same for my friend when he modifies a BSP I have everything disappearing except the Static Meshes.

We tried another version of Unreal 4.25.4 and still the same problem.

It’s an empty project with the starter content nothing more.

Can you help me?