Xamarin: Webview is not working for specific Http address

Question

I have an web application which needs to load in mobile apps.

i have used web view for loading web application.

it's working fine for non VPN network.

but while connecting to any VPN networks web view not supporting client specific URLs.

client is sung http based urls only.

Webview is showing blank screen while accessing the client specific http basaed url in ios app.

even i have tried to add NSExceptions domins list also, but no use. 

Can any one help out on this regard ?