The below Solution which i received from Koen Zwikstra below worked fine.. its perfect
If you need to reset the content in a modern frame, you need to set the ModernFrame.KeepContentAlive property to false. This effectively causes a reload every time content is loaded in a frame.
You can easily set the KeepContentAlive for all ModernFrames by specifying the following default style in App.xaml;
<Setter Property="KeepContentAlive" Value="False"/>