Problem in SelectedIndexChanged of gridview

Hi,

My requirement is, if i click on Manage button of gridview then it should show all the data in the textbox from database.

I have problem, It is working fine If contactusID visible="true" and when it is false then if i select row on gridview first time,its fine and if i select any row second time, i am getting error. There is no row at position 4 and my counter starts with 0, and i have 4 rows in my grid.

Code:-

protected void gvAppContactUs_SelectedIndexChanged(object sender, EventArgs e)
        {
            
            mvDefault.SetActiveView(vModifyApp);
            VModifyContactUsInView();
            hfIsNewContact.Value = false.ToString();
            NewContact(false);
            StyleUtility.EnableButton(btnDelete);
        }

protected void VModifyContactUsInView()
        {
            lblApplicationName.Text = hfSysName.Value;
            tcContactUs.ActiveTabIndex = 0;
            LinkApplicationSearch.Visible = true;
            LtrManageApplicationContactUs.Visible = false;
            LtrManageApplicationRoles.Visible = false;
            LtrRoleDetails.Visible = false;
            LtrSeparator0.Visible = false;
            LtrSeparator1.Visible = true;
            LtrSeparator2.Visible = true;
            LinkManageApplicationContactUs.Visible = true;
                        
            LinkManageApplicationContactUs.Text = gvApplications.SelectedDataKey["DisplayName"].ToString();
            LtrContactUsDetails.Visible = true;
            LtrContactUsDetails.Text = lblApplicationName.Text;
            ltrContactUsDetailsContactUsName.Visible = true;
            ltrContactUsDetailsContactUsName.Text = lblApplicationName.Text;
            btnContactUsDelete.Enabled = false;
            
            mvDefault.SetActiveView(vModifyContactUs);

            ApplicationContactUsDal dalContact = new ApplicationContactUsDal();
            DataTable dtContact = dalContact.GetAllContactUsInfo(hfSysName.Value);
                      
            String selectedContactUsID = gvAppContactUs.SelectedRow.Cells[0].Text;
            
            int selectedRowId;
            for (selectedRowId = 0; selectedRowId             {
                if ((dtContact.Rows[selectedRowId]["ContactUsID"].ToString()).Equals(selectedContactUsID))
                {
                    Session["contactUsID"] = selectedContactUsID;
                    break;
                }
            }
            hfContactUsID.Value = selectedContactUsID;

            hfApplicationName.Value = dtContact.Rows[selectedRowId]["ApplicationName"].ToString();
            txtOpenDaysOfWeek.Text = dtContact.Rows[selectedRowId]["OpenDaysOfWeek"].ToString();
            txtTimings.Text = dtContact.Rows[selectedRowId]["Timings"].ToString();
            txtTimeZone.Text = dtContact.Rows[selectedRowId]["TimeZone"].ToString();
            txtPhoneNumber.Text = dtContact.Rows[selectedRowId]["PhoneNumber"].ToString();
            txtPhoneNumber2.Text = dtContact.Rows[selectedRowId]["PhoneNumber2"].ToString();
            txtPhoneExtension.Text = dtContact.Rows[selectedRowId]["PhoneExtension"].ToString();
            txtEmailAddress.Text = dtContact.Rows[selectedRowId]["EmailAddress"].ToString();
            LinkManageApplicationContactUs.Text = gvAppContactUs.SelectedDataKey["ApplicationName"].ToString();
            tcPanelContactUsDetails.Visible = true;
            
           
            btnContactUsDelete.Enabled = false;
            gvAppContactUs.SelectedIndex = -1;
            
            lblApplicationName.Visible = true;
            
            BindAppContactUsGV();
            BindRoleWorkflow();
            SetBreadCrumbs();
         }

protected void BindAppContactUsGV()
        {

            // Get a list of Application ContactUs information
            List appContactUsInfo = new List(ContactUs.FindAllContactUsInfo(hfSysName.Value));

            // Sort Selected Roles
            switch (this.gvAppContactUs_sortOrder)
            {
                case "ContactUsID":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.ContactUsID).ToList();
                    break;

                case "ApplicationName":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.ApplicationName).ToList();
                    break;
                case "OpenDaysOfWeek":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.OpenDaysOfWeek).ToList();
                    break;
                case "Timings":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.Timings).ToList();
                    break;
                case "TimeZone":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.TimeZone).ToList();
                    break;
                case "PhoneNumber2":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.PhoneNumber2).ToList();
                    break;
                case "PhoneNumber":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.PhoneNumber).ToList();
                    break;
                case "PhoneExtension":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.PhoneExtension).ToList();
                    break;
                case "EmailAddress":
                    appContactUsInfo = appContactUsInfo.OrderBy(item => item.EmailAddress).ToList();
                    break;
            }

            if (this.gvAppContactUs_sortReverse)
            {
                appContactUsInfo.Reverse();
            }
            
            gvAppContactUs.DataSource = appContactUsInfo.ToArray();
            gvAppContactUs.DataBind();

           // String selectedContactUsID = gvAppContactUs.SelectedRow.Cells[0].Text;

            gvAppContactUs.Columns[0].Visible = false;  
            //tpAppContactUsInfo.TabIndex = 7;
            //Tabs.ActiveTab = vModifyApp.Controls[7];
            //Tabs.ActiveTabIndex = 7;
            //FreezeForContactUs(true);
      
        }

aspx code: -