Can't crop view in a drawing

Trying to crop a view of an assembly in a drawing...when I select the view the 'Crop' option is not available (grayed out).  I tried a bunch of things but I'm looking for suggestions.  FYI...the drawing is a copy/rename of another drawing.  There are several like this but I was able to use the 'Crop' feature in all except one.  Thanks in advance...Ed-SolidworksDrawings And Detailing