Triedron SetLabel Function won't display labels

Hi, I am creating a function to display the Triedron in the <0.0,0.0,0.0> point. The triedron is displayed fine with correct colors , but without "X" , "Y", "Z" labels How to fix? Where I am wrong? Thanks in advance, for any suggestion

This is the code:

Handle_AIS_Trihedron  MyOcc::createTrihedron()
{
        Handle_Geom_Axis2Placement axis = new Geom_Axis2Placement(gp::XOY()); 
        Handle_AIS_Trihedron aisTrihedron = new AIS_Trihedron(axis);
    aisTrihedron->SetDatumDisplayMode(Prs3d_DM_Shaded);
    aisTrihedron->SetDrawArrows(true);
    aisTrihedron->Attributes()->DatumAspect()->LineAspect(Prs3d_DP_XAxis)->SetWidth(2.5);
    aisTrihedron->Attributes()->DatumAspect()->LineAspect(Prs3d_DP_YAxis)->SetWidth(2.5);
    aisTrihedron->Attributes()->DatumAspect()->LineAspect(Prs3d_DP_ZAxis)->SetWidth(2.5);
    aisTrihedron->SetDatumPartColor(Prs3d_DP_XAxis, Quantity_NOC_RED2);
    aisTrihedron->SetDatumPartColor(Prs3d_DP_YAxis, Quantity_NOC_GREEN2);
    aisTrihedron->SetDatumPartColor(Prs3d_DP_ZAxis, Quantity_NOC_BLUE2);
    aisTrihedron->SetLabel(Prs3d_DP_XAxis,  "X" );
    aisTrihedron->SetLabel(Prs3d_DP_YAxis, "Y");
    aisTrihedron->SetLabel(Prs3d_DP_ZAxis, "Z");
    aisTrihedron->SetTextColor(Quantity_NOC_BLACK);
    aisTrihedron->SetSize(70);
    aisTrihedron->SetTransformPersistence(new Graphic3d_TransformPers(Graphic3d_TMF_ZoomPers, axis->Ax2().Location()));

     aisTrihedron->Attributes()->SetZLayer(Graphic3d_ZLayerId_Topmost);
    aisTrihedron->SetInfiniteState(true);
    return aisTrihedron;
}