Remplacer
With Sheets("Planning Ambulances Mensuel").Range("A4:T4")
.HorizontalAlignment = xlLeft
.VerticalAlignment = xlBottom
.Insert Shift:=xlDown
End With
par
Sheets("Planning Ambulances Mensuel").Range("A4:T4").Insert Shift:=xlDown
With Sheets("Planning Ambulances Mensuel").Range("A4:T4")
.HorizontalAlignment = xlLeft
.VerticalAlignment = xlBottom
End With