probleme sur graphique

Sub colorie()
With Selection.Border
        .ColorIndex = 3
        .Weight = xlThin
        .LineStyle = xlContinuous
    End With
End Sub

Option Explicit

Sub Macro1()
    Sheets("graph.mini-maxi").Select
    ActiveSheet.ChartObjects("Graphique1").Activate
    
    ActiveChart.SeriesCollection(1).Select
    With Selection.Border
        .ColorIndex = 43
        .Weight = xlThin
        .LineStyle = xlContinuous
    End With
    
    ActiveChart.SeriesCollection(2).Select
    With Selection.Border
        .ColorIndex = 6
        .Weight = xlThin
        .LineStyle = xlContinuous
    End With
    
    ActiveChart.ChartArea.Select
End Sub