Excel Macro to find unique distinct value based on Criteria

See the attached,

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim Rws As Long, Rng As Range, c As Range, s As String
    Dim rw1 As Long, r2 As Range, j19 As Range
    Dim rw2 As Long, r3 As Range, L19 As Range, c1 As Range, rng2 As Range
    Rws = Cells(Rows.Count, "A").End(xlUp).Row
    Set Rng = Range(Cells(2, 1), Cells(Rws, 1))
    Set rng2 = Range(Cells(2, 2), Cells(Rws, 2))


    Set j19 = Range("J19")
    Set L19 = Range("L19")
    If Target.Count > 1 Then Exit Sub
    If Target.Address = "$H$19" Then
        s = Target.Value

        Range("P4:P1000").ClearContents
        Range("R4:R1000").ClearContents

        '--------Country-------

        For Each c In Rng.Cells
            If c = s Then
                y = Application.WorksheetFunction.CountIf(Range(Cells(1, 2), Cells(c.Row, 2)), c.Offset(, 1))
                If y = 1 Then Cells(Rows.Count, "P").End(xlUp).Offset(1, 0) = c.Offset(0, 1)
            End If
        Next c
        rw1 = Cells(Rows.Count, "P").End(xlUp).Row
        Set r2 = Range(Cells(4, "P"), Cells(rw1, "P"))
        r2.Name = "cty"
        With j19.Validation
            .Delete
            .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
                 xlBetween, Formula1:="=cty"
        End With
    End If
    '--------Centers-------
    If Target.Address = "$J$19" Then
        s = Target.Value

        For Each c1 In rng2.Cells
            If c1 = s Then
                x = Application.WorksheetFunction.CountIf(Range(Cells(1, 3), Cells(c1.Row, 3)), c1.Offset(, 1))
                If x = 1 Then Cells(Rows.Count, "R").End(xlUp).Offset(1, 0) = c1.Offset(0, 1)
            End If
        Next c1
        rw2 = Cells(Rows.Count, "R").End(xlUp).Row
        Set r3 = Range(Cells(4, "R"), Cells(rw2, "R"))
        r3.Name = "ctr"
        With L19.Validation
            .Delete
            .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
                 xlBetween, Formula1:="=ctr"
        End With
    End If


End Sub