Column formatting working in Libreoffice, not excel 365

[akobberup]

I create a file with 4 columns formatted as datetime, date, number and decimal.

When opening in excel (online) the columns are not formatted:

When opening in libreoffice it works.

If i open the file in libreoffice and saves it, then the formatting will work in excel when opened there.

Here is the styling routine i use:

		for (int index = 0; index < headerElements.size(); index++) {
			final HeaderElement dataElement = headerElements.get(index);
			ColumnStyleSetter style = worksheet.style(index);
			style.fontSize(10);
			switch (dataElement.getDataType()) {
				case Boolean:
					style.horizontalAlignment("center");
					break;
				case String:
					break;
				case Number:
					style.horizontalAlignment("right");
					style.format("#,##0");
					break;
				case Decimal:
					style.horizontalAlignment("right");
					style.format("#,##0.00");
					break;
				case Date:
					style.format("yyyy/mm/dd");
					break;
				case DateTime:
					style.format("yyyy/mm/dd HH:mm");
					break;
			}
			style.set();
		}

Edit: Just to clarify, I'm danish, and we use period for thousand separator and comma as decimal separator :)

test5581114334280939970.xlsx

[MrAlucardDante]

I encountered the same issue.
Setting the style both with ColumeStyleSetter and StyleSetter (on each cell) worked in both Excel and LibreOffice
For instance :

ws.style(row, column).format(date_format).set();
ws.style(column).format(date_format).set();