How to get Error Message When VPN Disconnect

Question

I am working on the MAC Application in which I have to create the VPN Connection which I have Done Successfully.

Now I want to know the Reason If My VPN Disconnect.

When the VPN Disconnect I get the callback in my application and there I called the below code : SCNetworkConnectionCopyExtendedStatus

dicVPNFailureData =(__bridge NSDictionary *)(SCNetworkConnectionCopyExtendedStatus(connection));

Now this return me Dictionary as Below

{
    PPP =     {
        DeviceLastCause = 0;
        LastCause = 10;
        Status = 0;
    };
    Status = 0;
}

In this Dictionary, I receive the Disconnection cause in LastCause Key.

Now I want the message on the basis of that Code.

I also try the below code to get the Message but does not return message related to VPN Disconnection.

errorMessage = SCErrorString(strCode.intValue);

Is there any other way I can get the Error Message when my VPN Connection Disconnected.

Thanks for the help.