How to show tooltip for the tab header in WinForms TabbedMDIManager?

//Initialize
Form2 f1 = new Form2();
Form3 f2 = new Form3();
Form4 f3 = new Form4();
 
TabControlAdv tabcontrol;
tabbedMDIManager1.TabControlAdded += TabbedMDIManager1_TabControlAdded;
 
//TabStyle
tabbedMDIManager1.TabStyle = typeof(Syncfusion.Windows.Forms.Tools.TabRendererWorkbookMode);
 
//For MDI Forms
f1.MdiParent = this;
f1.Show();
f2.MdiParent = this;
f2.Show();
f3.MdiParent = this;
f3.Show();
 
private void TabbedMDIManager1_TabControlAdded(object sender, Syncfusion.Windows.Forms.Tools.TabbedMDITabControlEventArgs args)
{
  tabcontrol = args.TabControl;
  tabcontrol.ActiveTabColor = Color.Green;
  tabcontrol.ActiveTabForeColor = Color.White;
  tabcontrol.InactiveTabColor = Color.Brown;
  tabcontrol.InActiveTabForeColor = Color.Yellow;
  tabcontrol.TabPanelBackColor = Color.LightGray;
  tabcontrol.ItemSize = new Size(30, 30);
  if(tabcontrol != null)
  {
    //For Tooltip
    tabcontrol.MouseMove += Tabcontrol_MouseMove;
  }
}
 
private void Tabcontrol_MouseMove(object sender, MouseEventArgs e)
{
  for (int i = 0; i < tabcontrol.TabPages.Count; i++)
  {
    Rectangle r = tabcontrol.GetTabRect(i);
    if (r.Contains(e.Location) && toolTip1.GetToolTip(tabcontrol).ToString() != tabcontrol.TabPages[i].Text)
    {
      //Set ToolTip Text
      toolTip1.SetToolTip(tabcontrol, tabcontrol.TabPages[i].Text);
      break;
    }
  }
}

'Initialize 
Private f1 As New Form2()
Private f2 As New Form3()
Private f3 As New Form4()
 
Private tabcontrol As TabControlAdv
AddHandler tabbedMDIManager1.TabControlAdded, AddressOf TabbedMDIManager1_TabControlAdded
 
'TabStyle
tabbedMDIManager1.TabStyle = GetType(Syncfusion.Windows.Forms.Tools.TabRendererWorkbookMode)
 
'For MDI Forms
f1.MdiParent = Me
f1.Show()
f2.MdiParent = Me
f2.Show()
f3.MdiParent = Me
f3.Show()
 
Private Sub TabbedMDIManager1_TabControlAdded(ByVal sender As Object, ByVal args As Syncfusion.Windows.Forms.Tools.TabbedMDITabControlEventArgs)
  tabcontrol = args.TabControl
  tabcontrol.ActiveTabColor = Color.Green
  tabcontrol.ActiveTabForeColor = Color.White
  tabcontrol.InactiveTabColor = Color.Brown
  tabcontrol.InActiveTabForeColor = Color.Yellow
  tabcontrol.TabPanelBackColor = Color.LightGray
  tabcontrol.ItemSize = New Size(30, 30)
  If tabcontrol IsNot Nothing Then
    'For Tooltip
    AddHandler tabcontrol.MouseMove, AddressOf Tabcontrol_MouseMove
  End If
End Sub
 
Private Sub Tabcontrol_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs)
  For i As Integer = 0 To tabcontrol.TabPages.Count - 1
    Dim r As Rectangle = tabcontrol.GetTabRect(i)
    If r.Contains(e.Location) AndAlso toolTip1.GetToolTip(tabcontrol).ToString() <> 
tabcontrol.TabPages(i).Text Then
      'Set ToolTip Text
      toolTip1.SetToolTip(tabcontrol, tabcontrol.TabPages(i).Text)
      Exit For
    End If
  Next i
End Sub