When importing symbology from one layer to another layer in ArcMap, some of the features are not displayed in the target layer of the current map document. Symbology can be imported from an ArcGIS layer file (.lyr), a layer in the current map document, or an ArcView 3 legend file (.avl) using the Import button on the Symbology tab of the Layer Properties dialog box, or the Apply Symbology From Layer tool from ArcToolbox > Data Management Tools > Layers and Table Views.
This issue may occur due to one of the following reasons:
• Symbology in the source layer does not match the symbology in the target layer. For example, polygons cannot be symbolized with symbology used for points.
• The symbology between the target and source layers match, but the symbology definitions between the two layers do not match. For example, the feature class values are not the same as the values specified in the symbology.