Have you checked they are not Hidden or or Filtered Out?
Rebar elements that are cut by the cut plane are always visible. [Visibility States] has no effect on the visibility of these rebar instances.

Are there any plan regions in place?
Known issue previously where the plan region was only at a small part of the plan, but some sort of bug messed the rebar visibility up
Rebars not visible in view when a plan region is in view in Revit
Jay Colcombe
Autodesk Certified Instructor
Revit Architecture & Structure Certified Professional
AutoCAD Certified Professional
B.Sc. Hons Civil & Structural Engineering
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