Looks like busted LODs - personally I would just get rid of the affected hairs and find better stuff.
If you're set on keeping them, see if there's been any updates to those cc hairs and redownload them if so. It is possible to 'fix' them yourself but it involves downloading Sims 4 Studio and knowing how to use it (probably downloading blender as well but you shouldn't need to use it). The process involves exporting the working LOD for the hair and importing it over the missing/broken LODs. It's not difficult, just time consuming, and not best practices since those replacement meshes will be just as high poly as the high quality mesh (LOD0, the one that shows on close zoom).