dependent drop down list not working as it should

Formula:

Private Sub Worksheet_Change(ByVal Target As Range)

If Target.Count > 1 Then Exit Sub

If Not Intersect(Target, Range("a6")) Is Nothing Then

  Select Case Target

    Case "duo1"

      Application.EnableEvents = False

      Range("a7:c20").Value = Sheets("duo").Range("a6:c19").Value

      Application.EnableEvents = True

Formula:

 If Intersect(Target, Range("A7:A20, A38:A51, K7:K20, K38:K51, V7:V20, V38:V51")) Is Nothing Then Exit Sub

    Dim rng1 As Range

    Dim rng2 As Range

    Dim rng3 As Range

    Dim rng4 As Range

    Dim rng5 As Range

    

    

    For Each rng1 In Sheets("Gare").Range("A1:A92")

        If rng1 = Target Then

            With Cells(Target.Row, Target.Offset(0, 1).Column).Validation

                .Delete

                .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _

                    xlBetween, Formula1:="=Gare!$C$5:$C$16"

            End With

            With Cells(Target.Row, Target.Offset(0, 2).Column).Validation

                .Delete

                .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _

                    xlBetween, Formula1:="=Gare!$C$5:$C$16"

            End With

            Exit For

        End If

    Next rng1

once the data is transferred using the first code the second code should update the drop down lists but it will do so if i double click the target or entering it manually
it does not do it automatically.