case if combo box, add text, paragraph & style

hello Word forum peeps,

I was hoping someone could help me with this code?
when the combo box cmbEnclosure = "Yes" I would like to input the text "Encolosure: " and then a paragraph (this paragraph should be using the style "Heading 5"; bot not the text above)
If cmbEnclosure does not = "Yes" just text should be entered into the document
curently giving me a 'false' value in the document "Enclosure: (Nil)"

Dim strEnclosure As String
    Select Case cmbEnclosure.Text
    Case "Yes"
    strEnclosure = "Enclosure: " & vbCrLf & _
        Selection.Style = ActiveDocument.Styles("Heading 5")
    Case Else
    strEnclosure = "Enclosure: (Nil)"
    End Select

Thanks

Thanks Paul