C# Read and filter CSV file using LINQ

I am reading CSV file using LINQ and applying a filter then I am getting data but the problem is my count data is not always matching when comparing data after applying the same filter. I'm opening that CSV file with Excel but I could not determine why my count and excel data is not matching. so here I am pasting my full code with CSV file link. if possible please some one run my code after downloading the CSV file.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;

namespace WindowsFormsApplication1
{

    public partial class Form1 : Form
    {
        DataTable oData = null;
        public Form1()
        {
            InitializeComponent();

            oData = new DataTable();
            oData.Columns.Add("Date", typeof(string));
            oData.Columns.Add("Time", typeof(string));
            oData.Columns.Add("Incomming", typeof(string));
            oData.Columns.Add("Outgoing", typeof(string));
            oData.Columns.Add("Miss Call", typeof(string));
        }

        private void button1_Click(object sender, EventArgs e)
        {
            TimeSpan StartTime;
            TimeSpan EndTime;
            bool flag=true;
            TimeSpan tsStart = new TimeSpan(09, 00, 00);
            TimeSpan tsEnd = new TimeSpan(17, 30, 0);

            List<PhoneData> oPhoneData = GetPhoneData(@"d:\report.csv");
            bool isFirstTime = false;

            oData.Rows.Clear();
            while (tsStart < tsEnd)
            {
                if (!flag)
                {
                    tsStart = new TimeSpan(tsStart.Hours, tsStart.Minutes, int.Parse("01"));
                }
                flag = false;

                StartTime = tsStart;
                tsStart = tsStart.Add(new TimeSpan(00, 30, 00));
                EndTime = TimeSpan.Parse((tsStart.Hours >= 10 ? tsStart.Hours.ToString() : ("0" + tsStart.Hours.ToString())) 
                    + ":" + (tsStart.Minutes >= 10 ? tsStart.Minutes.ToString() : ("0" + tsStart.Minutes.ToString())) + ":00");


                int incomingCount = (from row in oPhoneData
                                     where row.direction == "I"
                                     && row.Call_Start.TimeOfDay >= StartTime
                                     && row.Call_Start.TimeOfDay <= EndTime
                                     && row.Is_Internal == 0
                                     && row.continuation == 0
                                     && row.call_duration.TotalSeconds > 0
                                     && !row.party1name.Contains("Voice Mail")
                                     && !row.party1name.Contains("VM")
                                     select 1).Count();

                int outgoingCount = (from row in oPhoneData
                                     where row.direction == "O"
                                     && row.Call_Start.TimeOfDay >= StartTime
                                     && row.Call_Start.TimeOfDay <= EndTime
                                     && row.Is_Internal == 0
                                     && row.continuation == 0
                                     && row.party1name != "Voice Mail"
                                     && !row.party1name.StartsWith("VM")
                                     select 1).Count();

                int misscallCount = (from row in oPhoneData
                                     where row.direction == "I"
                                     && row.continuation == 0
                                     && row.Caller.Trim() != string.Empty
                                     && row.Call_Start.TimeOfDay >= StartTime
                                     && row.Call_Start.TimeOfDay <= EndTime
                                     && row.party1name != "Voice Mail"
                                     && !row.party1name.StartsWith("VM")
                                     && !row.party1name.StartsWith("Line")
                                     && row.Park_Time == 0
                                     && row.Called_number == "687220"
                                     select 1).Count();


                DataRow dr = oData.NewRow();
                dr["Date"] = "12-04-2016";
                dr["Time"] = StartTime + "-" + EndTime;
                dr["Incomming"] = incomingCount;
                dr["Outgoing"] = outgoingCount;
                dr["Miss Call"] = misscallCount;
                oData.Rows.Add(dr);
            }
            dgList.DataSource = oData;
            MessageBox.Show("Job Done");
        }

        public List<PhoneData> GetPhoneData(string strFileName)
        {
            return File.ReadLines(strFileName)
                .Skip(1)
                .Where(s => s != "")
                .Select(s => s.Split(new[] { ',' }))
                .Select(a => new PhoneData
                {
                    Call_Start = DateTime.Parse( a[0]),
                    call_duration = TimeSpan.Parse(a[1]),
                    Ring_duration = int.Parse(a[2]),
                    direction = a[4],
                    Is_Internal =Convert.ToInt32( a[8]),
                    continuation = int.Parse( a[10]),
                    party1name = a[13],
                    Caller = a[3],
                    Park_Time = Convert.ToInt32(a[16]),
                    Called_number = a[5]
                })
                .ToList();
        }
    }

    public class PhoneData
    {
        public DateTime Call_Start { get; set; }
        public TimeSpan call_duration { get; set; }
        public Int32 Ring_duration { get; set; }
        public string direction { get; set; }
        public Int32 Is_Internal { get; set; }
        public Int32 continuation { get; set; }
        public string party1name { get; set; }
        public string Caller { get; set; }
        public Int32 Park_Time { get; set; }
        public string Called_number { get; set; }
    }
}