@sham.summan
This a recurring error since Revit 2013...seen it also/at least in versions 2014/15/18. It could be triggered by various reasons, no one really knows the actual cause (except probably Autodesk Development team)
Sometimes reproducing the color scheme and changing condition from a shared parameter to a project parameter helps, other times disabling the color scheme prevents it from happening.
Having no clue what is in your model, makes it even impossible to know what is going on. Therefore, if you cannot share the model, I would suggest that you report it as a bug and wait for Autodesk's reply
