Fatal error: Uncaught Error: Class 'PhpOffice\PhpSpreadsheet\Writer\Xlsx\WriterPart' not found in /var/www/app/appregwebservice/vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Writer/Xlsx/RelsRibbon.php:9 Stack trace: #0 {main} thrown in /var/www/app/appregwebservice/vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Writer/Xlsx/RelsRibbon.php on line 9