Fatal error: Uncaught PhpOffice\PhpSpreadsheet\Exception: Invalid cell coordinate K in C:\Apache24\htdocs\vendor\phpoffice\phpspreadsheet\src\PhpSpreadsheet\Cell\Coordinate.php:40 Stack trace: #0 C:\Apache24\htdocs\vendor\phpoffice\phpspreadsheet\src\PhpSpreadsheet\Style\Style.php(204): PhpOffice\PhpSpreadsheet\Cell\Coordinate::coordinateFromString('K') #1 C:\Apache24\htdocs\ProgNovo\prognovo03.php(34): PhpOffice\PhpSpreadsheet\Style\Style->applyFromArray(Array) #2 {main} thrown in C:\Apache24\htdocs\vendor\phpoffice\phpspreadsheet\src\PhpSpreadsheet\Cell\Coordinate.php on line 40