After unreal studio restart, lightmaps are messed up

Hello everyone,

I have baked my lighting and it has worked well and I was happy with it. then I had to restart my computer for some reason and when I open unreal studio again, my lightmaps were all messed up.
some of the objects turned black and some of them turned white.

I am using unreal studio with datasmith and all the uv’s are fine and the lightmap index coordinate is also fine. I did nothing but just restarted my computer and every thing has loses its lighting data.
after the bake it came out very well.

then last night i rebuild the lighting again to see whether its lightmap error or something else. today morning when i checked, the lightmap building were finished and the result was the same. means those objects who were black and white before is the same after the second build as well.

Can you please help me how can i rectify this problem?
thank you soooooooooooooooooooooo much

I have attached an image after the second bake. it means that the lightmaps data was fine in the first place but may there is a datasmith bug or something.