Failed to access WCF service over VPN!

Here is a script, im on network A and I am using a vpn client to connect network B to access a web service that can be accessed on network B. Even though I connected to network B, they were unable to access the webservice link. I need to tweak any settings.

But if ur is originally on network B and even if you connected to network A using a vpn client, they managed to access the webservice link. But the other way doesn't work.