Word automation loop problem

private void VelizinBelDok()
{
    try
    {
        System.Threading.Thread.Sleep(100);
        Cursor.Current = Cursors.WaitCursor;

        int iTotalFields = 1;
        Object oMissing = System.Reflection.Missing.Value;
        Object oTrue = true;
        Object oFalse = false;
        Word.Application oWord = new Word.Application();
        Word.Document oWordDoc = new Word.Document();
        oWord.Visible = true;
        oWord.WindowState = Word.WdWindowState.wdWindowStateMinimize;
        oWord.WindowState = Word.WdWindowState.wdWindowStateMaximize;
        Object oTemplatePath = System.Windows.Forms.Application.StartupPath + "\\Belgeler\\VelizinBel.docx";

        using (var conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source = gezievrak2541.accdb; Jet OLEDB:Database Password = Fatih2541; Mode = ReadWrite"))
        {
            conn.Open();

            using (var cmd = new OleDbCommand("Select * from gezilistemiz25,gezibilgileri25 WHERE unvani='Öğrenci'", conn))
            {
                using (OleDbDataReader dr = cmd.ExecuteReader())
                {
                    if (dr.HasRows)
                    {
                        while (dr.Read())
                        {
                            oWordDoc = oWord.Documents.Add(ref oTemplatePath, 
                               ref oMissing, ref oMissing, ref oMissing);

                            foreach (Word.Field myMergeField in oWordDoc.Fields)
                            {
                                iTotalFields++;
                                Word.Range rngFieldCode = myMergeField.Code;
                                String fieldText = rngFieldCode.Text;

                                if (fieldText.StartsWith(" MERGEFIELD"))
                                {
                                    Int32 endMerge = fieldText.IndexOf("\\");
                                    Int32 fieldNameLength = fieldText.Length - endMerge;
                                    String fieldName = fieldText.Substring(11, endMerge - 11);
                                    fieldName = fieldName.Trim();                                     

                                    if (fieldName == "sinifi")
                                    {
                                        myMergeField.Select();
                                        
                            oWord.Selection.TypeText(dr["sinifi"].ToString());
                                    }

                                    if (fieldName == "ono")
                                    {
                                        myMergeField.Select();
                                        
                            oWord.Selection.TypeText(dr["ono"].ToString());
                                    }

                                    if (fieldName == "adi")
                                    {
                                        myMergeField.Select();
                                        
                            oWord.Selection.TypeText(dr["adi"].ToString());
                                    }

                                    if (fieldName == "soyadi")
                                    {
                                        myMergeField.Select();
                                        
                            oWord.Selection.TypeText(dr["soyadi"].ToString());
                                    }

                                    if (fieldName == "gtarihi")
                                    {
                                        myMergeField.Select();
                                        oWord.Selection.TypeText(DateTime.Parse(dr["gtarihi"].ToString()).ToShortDateString());
                                    }

                                    if (fieldName == "dtarihi")
                                    {
                                        myMergeField.Select();
                                        oWord.Selection.TypeText(DateTime.Parse(dr["gezilistemiz25.dtarihi"].ToString()).ToShortDateString());
                                    }

                                    if (fieldName == "gyeri")
                                    {
                                        myMergeField.Select();
                                        oWord.Selection.TypeText(dr["gyeri"].ToString());
                                    }
                                }                               
                            }
                            
                            oWordDoc.Activate();
                            oWord.Activate();
                         }

                        //conn.Close();
                        //cmd.Dispose();
                        //conn.Dispose();
                        oWord.ActiveDocument.SaveAs2(Path.Combine
(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "Veli İzin Belgesi.docx"));
                        oWordDoc.Close(ref oFalse, ref oMissing, ref oMissing);
                        oWord.Quit();
                        System.Runtime.InteropServices.Marshal.ReleaseComObject(oWordDoc);
                        System.Runtime.InteropServices.Marshal.ReleaseComObject(oWord);
                        oWordDoc = null;
                        oWord = null;
                        //GC.WaitForPendingFinalizers();
                        //GC.Collect();
                        Cursor.Current = Cursors.Default;
                        MessageBox.Show("Veli İzin Belgesi 
                        Word formatında masaüstüne kaydedildi!");
                    }
                }
            }
        }
    }
    catch (Exception hata)
    {
        MessageBox.Show("İşlem Sırasında Hata Oluştu." + hata.Message);
    }
    }