Tessellation Cracks on mesh

I’m trying to use tesselation on model which I made for my project but in one place I encountered problem, tessellation is causing cracks on mesh, despite having checked “Crack free displacement” in material properties. I tend to assume its model problem since same material applied in different place doesn’t cause issues and works perfectly, but on other hand roof part of model is made out of single box in 3ds Max. Thanks for any insight on this.

Tesselation distance: 0, Tesselation Multiplier:1.0

Tesselation distance: 2, Tesselation Multiplier:1.0

Material setup