Generate PDF ReportView

I've taken an example ( link ) to generate PDF of a report. The example worked, but I have other reports that need to pass parameters, if I put only to view in the ReportView with the parameters works, but when I add the function generate PDF, it generates error saying that the parameter was not passed.

Follow my code:

            List<ReportParameter> listaParametro = new List<ReportParameter>();

        listaParametro.Add(new ReportParameter("Matricula", "351"));
        listaParametro.Add(new ReportParameter("Prefixo", "45072"));
        listaParametro.Add(new ReportParameter("SemanaIni", "201750"));

        reportViewer1.ServerReport.SetParameters(listaParametro);

 NetworkCredential myCred = new NetworkCredential("user", "senha");
        reportViewer1.ServerReport.ReportServerCredentials.NetworkCredentials = myCred;

        Warning[] warnings;
        string[] streamids;
        string mimeType;
        string encoding;
        string filenameExtension;

        byte[] bytes = reportViewer1.ServerReport.Render(
            "PDF", null, out mimeType, out encoding, out filenameExtension,
            out streamids, out warnings);

        using (FileStream fs = new FileStream("C:\Users\paulo\Desktop\Teste_Gera_Relatorio.pdf", FileMode.Create))
        {
            fs.Write(bytes, 0, bytes.Length);
        }

        System.Diagnostics.Process.Start("output.pdf");