Report Viewer does not present data

I managed to do everything correctly in the Oracle connection and everything works for me, but when the web form appears, the report viewer reports nothing. This is my code:

using System;
using System.Data;
using System.Data.OleDb;
using Microsoft.Reporting.WebForms;


namespace VisorRpt.Reportes
{
    public partial class Visor : System.Web.UI.Page
    {
        private string Txt;
        private string oradb = "Provider=OraOLEDB.Oracle;Data Source=UMBD;User Id=DESAUMBRELLA;Password=USERDESA;";
        public static OleDbConnection Conn;
        protected void Page_Load(object sender, EventArgs e)
        {
            // el valor del reporte y de la empresa debe ser pasado
            int  NRep = 182;            // Número reporte
            string NEmp = "C145";       // Código empresa
            string NomE;                // Nombre de la empresa (Pendiente)
            double Tot;
            DataTable dt;
            OleDbDataAdapter da;
            OleDbConnection Conn= new OleDbConnection(oradb);
            Conn.Open();
            DataSet ds = new DataSet();
            Txt = string.Concat("SELECT * FROM M_TIPO_REPORTE WHERE TIPO_REP_ID=",NRep);
            da = new OleDbDataAdapter(Txt,Conn);
            dt = new DataTable();
            da.Fill(dt);
            // Comando SQL almacenado
            string XSel = Convert.ToString(dt.Rows[0]["SQL_T_REP"]);
            da.Dispose();
            dt.Dispose();
            if (NRep == 182)      // Ventas Extendidas
            {
                Vrx.Text = "Variantes:";
                DDVrx.Items.Add("Cliente");
                DDVrx.Items.Add("Proveedor");
                DDVrx.Items.Add("Vendedor");
                DDVrx.Items.Add("Producto");
                DDVrx.Items.Add("Agencia");
                Txt = string.Concat("SELECT COM_ID,NOM_CLIENTE,SUM(SUBTOTAL) as Stot FROM VM_VENTAS_EXT WHERE "
                    + "COM_ID='", NEmp, "' GROUP BY COM_ID,NOM_CLIENTE");
                da = new OleDbDataAdapter(Txt, Conn);
                dt = new DataTable();
                da.Fill(dt);
                Tot = Convert.ToDouble(dt.Rows[0]["Stot"]);         // Total Ventas
                //NomE = Convert.ToString(dt.Rows[0][]);            // Nombre empresa
                da.Dispose();
                dt.Dispose();
                RV.LocalReport.DataSources.Clear();
                Txt = string.Concat("SELECT COM_ID, NOM_CLIENTE AS NOMBRE, TARIFA, SUBTOTAL, (SUM(V.SUBTOTAL)/", Tot, ") *100 AS STOT, (SUM(V.TARIFA)/", Tot, "1)*100 AS TAR "
                    + "FROM VM_VENTAS_EXT WHERE COM_ID='", NEmp, "' GROUP BY COM_ID,NOM_CLIENTE");
                da = new OleDbDataAdapter(Txt, Conn);
                dt = new DataTable();
                ReportDataSource dataB = new ReportDataSource("Ventas", dt);
                // Ojo en esta linea hay que colocar el path definitivo
                RV.LocalReport.ReportPath = @"\umbrella.local\dfs\data_user\desarrollo1\Documents\Visual Studio 2015\Projects\VisorRpt\VisorRpt\Reportes\RptVentas.rdlc";
                var Titulo = new ReportParameter();
                var Vtas = new ReportParameter();
                RV.LocalReport.SetParameters(new ReportParameter[] { Titulo, Vtas });
                RV.LocalReport.DataSources.Add(dataB);
                **RV.LocalReport.Refresh();**
            }
        }
    }
}

Even though the Refresh is executed and I have all the Oracle's permissions, it only presents the web page with a couple of controls that I placed to filter later. I appreciate any help.