private async void DoRefresh(object obj)
        {
            Loading   = true;
            Workflows = new ObservableCollection <QueryWorkflowVM>();
            Workflows.CollectionChanged += Workflows_CollectionChanged;
            try
            {
                var result = await RestHub.QueryWorkflows();

                if (result.UserObject != null)
                {
                    List <QueryWorkflowUserDTO> dto = result.UserObject as List <QueryWorkflowUserDTO>;
                    if (dto != null)
                    {
                        foreach (var username in Usernames)
                        {
                            var workflow = dto.Where(w => w.L1User == username).FirstOrDefault();
                            Workflows.Add(new QueryWorkflowVM
                            {
                                L1user = username,
                                L2user = workflow?.L2User,
                                L3user = workflow?.L3User,
                                L4user = workflow?.L4User,
                                L5user = workflow?.L5User,
                            });
                        }
                        Workflows.UpdateDisplayOrder();
                    }
                }
                else
                {
                    MessageBox.Show("Can't Load Users . .");
                }
            }
            catch (Exception ex)
            {
                AppErrorBox.ShowErrorMessage("Error While Loading Users . .", ex.ToString());
            }
            Loading = false;
        }