Do the missing layers show up in other views, or when you travel down layer by layer?
Very occasionally in a few models I also had similar gaps in the layer-view, in an old Cura version. But this was just a rendering issue in Cura. In other views (normal, transparant, x-ray) everything showed up okay, and when viewing the missing parts layer by layer, they also showed up correctly; and most important: they printed fine.
If they are also missing in all other views, or shown in red in x-ray view, then obviously it is a model-issue.
Try the "fix horrible" settings in expert settings. That *might* help.
Basically your model is not manifold meaning it has inerior structures or more likely some holes in the outer surface. That's fine for a visual-only model but not fine for something you want to print. Cura doesn't know inside from outside - a human knows instantly that the inside would be roughly the area just above the layer below. But cura doesn't know.
If you look at the model in cura xray view it will show your problem spots in red/brown colors. That way you can zoom in and find the missing (or extra) surfaces.
Or alternatively there are packages that fix models. Free websites. google "how do I make my STL manifold".
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