I have the following code:

```
$spreadsheet = new Spreadsheet();
$sheet = $spreadsheet->getActiveSheet();
$sheet->getPageSetup()->setOrientation(PageSetup::ORIENTATION_LANDSCAPE);
$sheet->getPageMargins()
    ->setLeft(0.1)
    ->setRight(0.1)
    ->setTop(0.1)
    ->setBottom(0.1)
    ->setHeader(0);
$sheet->setCellValue('A1', 'Test input');

$writer = new Mpdf($spreadsheet);
$dateStamp = Carbon::now()->format('YmdHis');
$saveDirectory = REPORTS_DIR . Auth::user()->getAuthIdentifier() . '/';
if (is_dir($saveDirectory) === false) {
    mkdir($saveDirectory, 755, true);
}
$writer->save($saveDirectory . $dateStamp . '-global.pdf');

```

The margines aren't being set correctly. I have set it to huge number and tiny numbers (as above) and none of them update the printed pdf document. When I swop out the Mpdf writer for an Xlsx writer, the margins work and when I change it, it updates the spreadsheet accordingly.

Is there some other way that I need to set the margins for it to update on the pdf size?