Cortana goes to bing for specific commands

Question

Cortana is not working for 'what is engineering' but working for 'what is gravity' even though VCD file is loaded without exceptions. The commands are registered under 'what can i say' page.

Changes are done above the sample code given at https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/CortanaVoiceCommand

AdventureWorksCommand.xml

<?xml version="1.0" encoding="utf-8" ?>
<VoiceCommands xmlns="http://schemas.microsoft.com/voicecommands/1.2">
<CommandSet xml:lang="en-in" Name="AdventureWorksCommandSet_en-in">
<AppName> ask assistant</AppName>
<Example> what is gravity </Example>

<Command Name="q1">
  <Example>what is engineering</Example>
  <ListenFor RequireAppName="BeforeOrAfterPhrase">what is engineering</ListenFor>
  <Feedback> Let me check that for you</Feedback>
  <VoiceCommandService Target="AdventureWorksVoiceCommandService"/>
</Command>
<Command Name="q2">
  <Example>what is gravity</Example>
  <ListenFor RequireAppName="BeforeOrAfterPhrase">what is gravity</ListenFor>
  <Feedback> Let me check that for you</Feedback>
  <VoiceCommandService Target="AdventureWorksVoiceCommandService"/>
</Command>

In AdventureWorksVoiceCommandService.cs, default part of switch case connects to a third party service and gets response,

try
            {
                voiceServiceConnection =
                    VoiceCommandServiceConnection.FromAppServiceTriggerDetails(
                        triggerDetails);

                voiceServiceConnection.VoiceCommandCompleted += OnVoiceCommandCompleted;

                // GetVoiceCommandAsync establishes initial connection to Cortana, and must be called prior to any 
                // messages sent to Cortana. Attempting to use ReportSuccessAsync, ReportProgressAsync, etc
                // prior to calling this will produce undefined behavior.
                VoiceCommand voiceCommand = await voiceServiceConnection.GetVoiceCommandAsync();

                // Depending on the operation (defined in AdventureWorks:AdventureWorksCommands.xml)
                // perform the appropriate command.
                switch (voiceCommand.CommandName)
                {
                    case "whenIsTripToDestination":
                        var destination = voiceCommand.Properties["destination"][0];
                        await SendCompletionMessageForDestination(destination);
                        break;
                    case "cancelTripToDestination":
                        var cancelDestination = voiceCommand.Properties["destination"][0];
                        await SendCompletionMessageForCancellation(cancelDestination);
                        break;
                    //case "myBalance":
                    //    string result = "";
                    //    //string speech = "My Balance is 100 dollars great! My Balance is 100 dollars great!My Balance is 100 dollars great!";
                    //    string speech = voiceCommand.SpeechRecognitionResult.Text;
                    //    ApiAiService service = new ApiAiService();
                    //    result = await service.getResult(speech);
                    //    await SendMessageToPlay(result);
                    //    //ApiAiService service = new ApiAiService();
                    //    //s.PlayMedia("You are doing great, your balance is 100 dollars");
                    //    break;
                    default:
                        // As with app activation VCDs, we need to handle the possibility that
                        // an app update may remove a voice command that is still registered.
                        // This can happen if the user hasn't run an app since an update.
                        //LaunchAppInForeground();
                        string result = "";
                        //string speech = "My Balance is 100 dollars great! My Balance is 100 dollars great!My Balance is 100 dollars great!";
                        string speech = voiceCommand.SpeechRecognitionResult.Text;
                        ApiAiService service = new ApiAiService();
                        result = await service.getResult(speech);
                        await SendMessageToPlay(result);
                        break;
                }
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine("Handling Voice Command failed " + ex.ToString());
            }