Fatal error: Uncaught Error: Class "PhpOffice\PhpSpreadsheet\Style\Supervisor" not found in C:\xampp\htdocs\xlsss\PhpSpreadsheet-master\src\PhpSpreadsheet\Style\Font.php:7 Stack trace: #0 {main} thrown in C:\xampp\htdocs\xlsss\PhpSpreadsheet-master\src\PhpSpreadsheet\Style\Font.php on line 7