Fatal error: Uncaught Error: Class 'Box\Spout\Writer\WriterAbstract' not found in /var/www/html/portal/vendora/box/spout/src/Spout/Writer/WriterMultiSheetsAbstract.php:23 Stack trace: #0 {main} thrown in /var/www/html/portal/vendora/box/spout/src/Spout/Writer/WriterMultiSheetsAbstract.php on line 23