context menu problem in vb.net?

Private Sub InitializeMyContextMenu()
        ' Create the contextMenu and the MenuItem to add.
        Dim contextMenu1 As New ContextMenu()
        Dim mnuItemCut As New MenuItem("Cut")
        Dim mnuItemCopy As New MenuItem("&Copy")
        Dim mnuItemPaste As New MenuItem("&Paste")

        ' Use the MenuItems property to call the Add method
        ' to add the MenuItem to the MainMenu menu item collection. 
        contextMenu1.MenuItems.Add(mnuItemCut)


        contextMenu1.MenuItems.Add(mnuItemCopy)
        contextMenu1.MenuItems.Add(mnuItemPaste)

        ' Assign mainMenu1 to the rich text box.
       richtxtbox1.ContextMenu = contextMenu1
    End Sub

  Private Sub mnuItemCopy_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuItemCopy.Click
        txtSRFormD_Instructions.Copy()

    End Sub
    Private Sub mnuItemCut_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuItemCut.Click
        txtSRFormD_Instructions.Cut()
      
    End Sub