Combo Box triggers another comboxbox display

[dr223]

 If CmbTruckTyp.SelectedIndex > -1 Then

            Select Case Me.CmbTruckTyp.SelectedItem.ToString

                Case "MERCEDES-BENZ"
                    cmbMercBenzModels.Visible = True
                    cmbDafModels.Visible = False
                Case "DAF"
                    cmbMercBenzModels.Visible = False
                    cmbDafModels.Visible = True
                Case Else
                    cmbMercBenzModels.Visible = False
                    cmbDafModels.Visible = False

            End Select

At runtime, no errors, however, when I select DAF, cmbDafModels.Visible is not set True , same applies when I select MERCEDES-BENZ, cmbMercBenzModels.Visible is not set to True.

Why?


Any help -- thanks