.NET: Storing Datatable with parametrized stored procedure using ODBC

Question

Stuck filling a datatable. Is it about filling the datatable?, Is it about passing parameters?, is it about a procedure with out sys_refcursor? Tried this:

public DataTable ConnectAndQuery(string layerName, decimal idElemento, string idElementoString, string conexion)
{
    Logger.Debug("App_Code/ConexionBD.cs: using (OdbcConnection connection = new OdbcConnection(Driver={Microsoft ODBC for Oracle}; + conexion ");
    using (OdbcConnection conn = new OdbcConnection(conexion))
    {
        try
        {
            using (OdbcDataAdapter da = new OdbcDataAdapter())
            {
                da.SelectCommand = new OdbcCommand("{ call PKG_GEONET_REPORTS.GET_ORDINARY_CLIENT(?, ?, ?) }", conn);
                da.SelectCommand.CommandType = CommandType.StoredProcedure;
                //da.SelectCommand.CommandType = System.Data.CommandType.Text;

                da.SelectCommand.Parameters.AddWithValue("client_in", idElemento.ToString());
                da.SelectCommand.Parameters.AddWithValue("layer_in", layerName);
                da.SelectCommand.Parameters.AddWithValue("client_data", ParameterDirection.Output);

                DataSet ds = new DataSet();
                da.Fill(ds, "data");

                DataTable dt = ds.Tables["data"];

                /*foreach (DataRow row in dt.Rows)
                {
                    dt.Rows.Add(row);
                }*/
                return dt;
            }
        }
        catch (Exception ex)
        {
            throw (ex);
        }
    }
}

and this:

    public DataTable ConnectAndQuery(string layerName, decimal idElemento, string idElementoString, string conexion)
    {
        Logger.Debug("App_Code/ConexionBD.cs: using (OdbcConnection connection = new OdbcConnection(Driver={Microsoft ODBC for Oracle}; + conexion ");
        using (OdbcConnection conn = new OdbcConnection(conexion))
        {
            try
            {
                using (OdbcCommand Command = new OdbcCommand("{ call PKG_GEONET_REPORTS.GET_ORDINARY_CLIENT() }", conn))
                {
                    Command.CommandType = CommandType.StoredProcedure;
                    Command.Parameters.AddWithValue("client_in", idElemento.ToString());
                    Command.Parameters.AddWithValue("layer_in", layerName);
                    Command.Parameters.AddWithValue("client_data", ParameterDirection.Output);
                    using (OdbcDataAdapter da = new OdbcDataAdapter(Command))
                    {
                        DataTable dt = new DataTable();
                        da.Fill(dt);
                        return dt;
                    }
                }
            }
            catch (Exception ex)
            {
                throw (ex);
            }
        }
    }

I have no error message, my app couldn't show the result, I'm just seeing a blank screen.

my conexion string is:

"Driver={Microsoft ODBC for Oracle};...;"

and my stored procededure is:

PROCEDURE GET_ORDINARY_CLIENT (client_in IN varchar2, layer_in IN varchar2, client_data OUT SYS_REFCURSOR );