unable to parse barcode

[j-thiele-fs]

i have the problem that my scanner can't parse a barcode that contains two application identifiers. The barcode i generated for a sscc works fine, but it only contains one application identifier.
here is a snippet from my code. maybe i am using the library wrong?

private static char _fnc1 = (char)29;
public static Bitmap GenerateBestBeforeBatchId128EAN(string bestBeforeDate, string batchId)
{
    string debug = $"{_fnc1}(15){bestBeforeDate}{_fnc1}(10){batchId}";
    Logger.WriteDebugLog(debug);
    
	BarcodeWriter barcodeWriter = new BarcodeWriter
	{
		Format = BarcodeFormat.CODE_128,
		Options = new EncodingOptions
		{
			Width = _barcodeWidth,
			Height = _barcodeHeight,
			Margin = _margin,
			// controls if the content string appears in the output img
			PureBarcode = false
		}
	};
	barcodeWriter.Options.Hints[EncodeHintType.GS1_FORMAT] = true;
	return barcodeWriter.Write(data);BarcodeWriter barcodeWriter = new BarcodeWriter
	{
		Format = BarcodeFormat.CODE_128,
		Options = new EncodingOptions
		{
			Width = _barcodeWidth,
			Height = _barcodeHeight,
			Margin = _margin,
			// controls if the content string appears in the output img
			PureBarcode = false
		}
	};
	barcodeWriter.Options.Hints[EncodeHintType.GS1_FORMAT] = true;
	return barcodeWriter.Write($"{_fnc1}(15){bestBeforeDate}(10){batchId}");
}