MsgChannelUtilities: Value for argument "name" must be specified.

I'm wanted to send a prompt message to the front-end at the end of my business process.

FrontEnd (The debugger never get fired)

init: function() {
        this.callParent(arguments);
        this.subscriptionFunction();
      },
      subscriptionFunction: function() {    
        debugger
        Terrasoft.ServerChannel.on(Terrasoft.EventName.ON_MESSAGE, this.onMyProcessMessage, this);
      },
      onMyProcessMessage: function(scope, message) {
        debugger
 
        if (!message || message.Header.Sender !== "ShowSuccessDialog") {
          return;
        }
 
        var message2 = message.Body;
 
        if (!this.Ext.isEmpty(message2)) {
          this.Terrasoft.showInformation(message2);
        }
      },

Business Process

string sender = "ShowSuccessDialog";
string messageText = "Successful";
 
MsgChannelUtilities.PostMessageToAll(sender, messageText);
 
return true;	

- And I'm receiving this error.

The server encountered an error processing the request. The exception message is 'Value for argument "name" must be specified.'

What name could this error mean? Or is this totally not related to my goal?

Reference

- https://community.creatio.com/questions/refresh-page-fields-after-proce…

Best Regards.