<appSettings>
  <add key="HostServer" value="pop.gmail.com" />
  <add key="MailPort" value="995" />
  <add key="MailUser" value="your-email@gmail.com" />
  <add key="MailPwd" value="your-password" />
</appSettings>

public void ReadTheDataFromTheMail()
{
    try
    {
        string mailHost = ConfigurationManager.AppSettings["HostServer"];
        int mailPort = Convert.ToInt32(ConfigurationManager.AppSettings["MailPort"]);
        string mailID = ConfigurationManager.AppSettings["MailUser"];
        string mailPwd = ConfigurationManager.AppSettings["MailPwd"];

        using (Pop3Client client = new Pop3Client())
        {
            client.Connect(mailHost, mailPort, true);
            client.Authenticate(mailID, mailPwd);

            int messageCount = client.GetMessageCount();
            DateTime today = DateTime.UtcNow.Date;

            for (int i = messageCount; i > 0; i--)
            {
                MessageHeader headers = client.GetMessageHeaders(i);
                string subject = headers.Subject;
                DateTime emailDate = headers.DateSent;

                if (!string.IsNullOrEmpty(subject) && subject.Contains("AllotmentsFiles") && emailDate.Date == today)
                {
                    OpenPop.Mime.Message message = client.GetMessage(i);

                    foreach (var attachment in message.FindAllAttachments())
                    {
                        if (attachment.FileName.Contains("AllotmentsFiles_") && attachment.FileName.EndsWith(".csv"))
                        {
                            string baseDirectory = @"E:\Allotment - Applns\Allotmentfiles";
                            string dateFolder = DateTime.Now.ToString("yyyy-MM-dd");
                            string fileFolder = Path.Combine(baseDirectory, dateFolder);

                            if (!Directory.Exists(fileFolder))
                                Directory.CreateDirectory(fileFolder);

                            string filePath = Path.Combine(fileFolder, attachment.FileName);
                            File.WriteAllBytes(filePath, attachment.Body);

                            errorlog($"CSV file '{attachment.FileName}'", "Downloaded successfully!");
                            ProcessAllotmentData(filePath);
                        }
                    }
                }
            }
        }
    }
    catch (Exception ex)
    {
        errorlog("Error reading emails", ex.Message);
    }
}

public void ProcessAllotmentData(string filePath)
{
    try
    {
        string fileName = Path.GetFileName(filePath);
        string[] parts = fileName.Split('_');
        string scriptName = parts.Length > 0 ? parts[0] : null;

        using (StreamReader sr = new StreamReader(filePath))
        {
            string[] rows = sr.ReadToEnd().Split('\n');

            for (int i = 1; i < rows.Length; i++)
            {
                string[] rowValues = rows[i].Split(',');
                if (rowValues.Length > 7)
                {
                    string appNo = rowValues[2].Trim();
                    string pan = rowValues[4].Trim();
                    string qty = rowValues[5].Trim();
                    string clientName = rowValues[6].Trim();
                    string reason = rowValues[7].Trim();

                    SqlParameter[] param = {
                        new SqlParameter("@symbol", scriptName),
                        new SqlParameter("@appno", appNo),
                        new SqlParameter("@pan", pan),
                        new SqlParameter("@qty", qty),
                        new SqlParameter("@reason", reason)
                    };

                    string statusQuery = @"SELECT * FROM bidfiledetails  (NOLOCK)
                                           WHERE AppNo=@appno AND Symbol=@symbol AND PanNo=@pan AND AllotmentFlag != 'Y'";

                    DataSet ds = SqlHelper.ExecuteDataset(SqlCon, CommandType.Text, statusQuery, param);

                    if (ds.Tables[0].Rows.Count > 0)
                    {
                        string updateQuery = @"UPDATE bidfiledetails
                                               SET AllotmentFlag='Y', SharesAlloted=@qty, Sharesrej_reason=@reason
                                               WHERE AppNo=@appno AND PanNo=@pan AND Symbol=@symbol";

                        SqlHelper.ExecuteNonQuery(SqlCon, CommandType.Text, updateQuery, param);
                        errorlog("Updated Record", $"PanNo: {pan}, ApplicationNo: {appNo}, Symbol: {scriptName}");
                    }
                    else
                    {
                        string header = "ApplicationNo|ClientName|Quantity|Reason|PanNo";
                        string message = $"{appNo}|{clientName}|{qty}|{reason}|{pan}{Environment.NewLine}";
                        errorlog(header, message);
                    }
                }
                else
                {
                    errorlog("Row does not have enough columns", "");
                }
            }
        }
    }
    catch (Exception ex)
    {
        ExceptionLogging.Exceptionlog("Exception in ProcessAllotmentData", ex.Message);
    }
}