Remove rows from excel using Apache POI.

Hello Experts,
Am trying to modify an excel file having multiple rows using Apache POI 3.17 (i.e. remove the rows). When I tried to remove the rows in the first while loop, I used to receive the error concurrentmodificationexception. I tried moving all the rows into a list and then delete it in a separate loop as suggested in one of the forums. I now receive XmlValueDisconnectedException. Can anyone please suggest what might be going wrong here?

public static void removeFalseRows(String readFilePath, String writeFilePath, String sheetName) throws IOException, InvalidFormatException {
		List<Row> toRemove = new ArrayList<Row>();
		FileInputStream fsIP = new FileInputStream(new File(readFilePath));
		Workbook wb = WorkbookFactory.create(fsIP);
		Sheet sheet = wb.getSheet(sheetName);
		Iterator<Row> rowIterator = sheet.iterator();
		while (rowIterator.hasNext()) {
			Row row = rowIterator.next();

			if (row.getCell(5).toString().equals("false")) {
				toRemove.add(row);
			}
		}

		for(Row R : toRemove) {
			sheet.removeRow(R);
		}

		for(Row R : toRemove) {
			int rowIndex = R.getRowNum();
			int lastRowNum = sheet.getLastRowNum();
			if (rowIndex >= 0 && rowIndex < lastRowNum)
			{
				sheet.shiftRows(rowIndex + 1, lastRowNum, -1);
			}
		}