Radius and DistType properties in your sample below don't exist.

[Kevin]

My ImageryLayer Prperties, then your sample code 

<maps:ImageryLayer
                            x:Name="ThisImageLayer"
                            BingMapKey="xxx"
                            BingMapStyle="Road"
                            GeoCoordinates="38.328732,-85.764771"
                            LayerType="Bing"
                            MarkerSelected="Layer_MarkerSelected"
                            MarkerTemplate="{StaticResource Key=markerTemplate}">

<maps:SfMaps  x:Name="Map" >
        <maps:SfMaps.Layers >
            <maps:ImageryLayer MarkerSelected="Layer_MarkerSelected" GeoCoordinates = "38.909804, -77.043442" Radius="5" DistanceType="KiloMeter" MarkerTemplate="{StaticResource Key=markerTemplate}">
                <maps:ImageryLayer.Markers>
                    <maps:MapMarker Latitude= "38.909804" Longitude= "-77.043442"/>
                </maps:ImageryLayer.Markers>
            </maps:ImageryLayer>
        </maps:SfMaps.Layers>
    </maps:SfMaps>

[Ramya Soundar Rajan]

Hi Kevin, 

 

Greetings from Syncfusion. 

 

We have included the “Calculate a zoom level based on map geo-bounds or distance” support in Volume1 2020 beta release. So, could you please check with the updated version and clear the entire cache. 

 

Version: 18.1.0.36 

 

Please revert us if you still facing the problem on this. 

 

Regards, 

Ramya S