Flutter : Not able to print greek letters in receipt Sunmi K2

Question

I am trying to print a receipt for Sunmi K2 Pro. but the Greek letters are not printing. I am using below packages

sunmi_printer_plus: ^2.1.2
esc_pos_utils_plus: ^2.0.3
charset_converter: ^2.1.2

the printer code is as follows.

                          await SunmiPrinter.bindingPrinter();
                          final List<int> _escPos = await customEscPos();
                          await SunmiPrinter.initPrinter();
                          await SunmiPrinter.startTransactionPrint(true);
                          await SunmiPrinter.printRawData(
                              Uint8List.fromList(_escPos));
                          await SunmiPrinter.exitTransactionPrint(true);

customEscPos function is

 Future<List<int>> customEscPos() async {
      final profile = await CapabilityProfile.load();
      final generator = Generator(PaperSize.mm80, profile, );
    bytes +=generator.textEncoded(utf8.encode('         Συνολική Καθαρή Αξία:   EUR 10,72'));
      bytes +=generator.textEncoded(utf8.encode('                    Φ.Π.Α 24%:    EUR 2,15'));
      bytes +=generator.textEncoded(utf8.encode('                    Φ.Π.Α 13%:    EUR 0,23'));
      bytes +=generator.textEncoded(utf8.encode('E                Πληρωτέο Ποσό:   EUR 13,10'));
bytes += generator.reset();
  bytes += generator.cut();

  return bytes;
    }