I generate report design by code but khmer font not display correct

 Dictionary<String, String> parameters = new Dictionary<String, String>();
 parameters["OrderType"] = Base.Document.Current.OrderType;
 parameters["RefNbr"] = Base.Document.Current.OrderNbr;
 //Report Processing
 PXReportSettings settings = new PXReportSettings(rowExt.UsrDefReport);
 PX.Reports.Controls.Report _report = ReportLoader.CheckIfNull(nameof(ReportLoader)).LoadReport(rowExt.UsrDefReport, null);
 ReportLoader.InitReportParameters(_report, parameters, settings, false);
 PX.Reports.Data.ReportNode reportNode = ReportDataBinder.CheckIfNull(nameof(ReportDataBinder)).ProcessReportDataBinding(_report);
 //Generation PDF
 byte[] data = PX.Reports.Mail.Message.GenerateReport(reportNode, RenderType.FilterPdf).First();

 if (!salesPersonExt.UsrBotID.IsNullOrEmpty())
 {
     Helper.SendByTelegramWithFile(salesPersonExt.UsrBotID, data, Base.Document.Current.OrderNbr, "Sales Order: " + Base.Document.Current.OrderNbr);
 }

but print report in ui show correctly display