ArcGIS Urban: No layer symbology found

Error Message

In ArcGIS Urban, attempts to select a feature layer to upload zoning boundaries when creating an urban model fail, and the following error is returned:

Error:   
No layer symbology found
The selected layer has no sublayers that can be imported.

Cause

The imported layer does not have the correct symbology applied. This commonly occurs when the layer is published from ArcGIS Pro to ArcGIS Online or the ArcGIS Enterprise portal as a shapefile, and the symbology is not retained.

Solution or Workaround

Open the item page of the hosted feature layer in ArcGIS Online or the ArcGIS Enterprise portal, and set the styling type to a unique symbols style through the Visualization tab. Refer to Steps 3 through 11 in ArcGIS Online: Apply a style or Portal for ArcGIS: Apply a style for instructions.

Note:
Alternatively, change the symbology of the feature layer to unique values in ArcGIS Pro before publishing to ArcGIS Online or the ArcGIS Enterprise portal as a feature layer.