XL 2016 créer une alerte

=NB.SI.ENS(Nom;$D2;Prénoms;$F2)>0

Sub Worksheet_Change(ByVal Target As Range)
    If Target.Count > 1 Then Exit Sub
    If Not Intersect(Target, Range("D2:F10000")) Is Nothing Then
        On Error GoTo Fin
        Application.ScreenUpdating = False: Application.EnableEvents = False
        Set Plage = Range("D2:F" & Range("D65500").End(xlUp).Row)
        Plage.FormatConditions.Delete
        Plage.FormatConditions.Add(Type:=xlExpression, _
        Formula1:="=NB.SI.ENS(Nom;INDEX($D:$D;LIGNE());Prénoms;INDEX($F:$F;LIGNE()))>0").Interior.Color = vbRed
    End If
Fin:
    Application.EnableEvents = True: Application.ScreenUpdating = True
End Sub