I am't able to create PDF file

[allamsettiramesh]

I am getting below issue and my folder has 777 permissions ...Fatal error: Uncaught RuntimeException: Failed to write to file "./dssss.pdf". in /var/www/html/pdf/vendor/gears/pdf/src/Pdf.php:208 Stack trace: #0 /var/www/html/pdf/vendor/gears/pdf/src/Pdf.php(168): Gears\Pdf->save('./dssss.pdf') #1 /var/www/html/pdf/pdf.php(9): Gears\Pdf::convert('./docs.docx', './dssss.pdf') #2 {main} thrown in /var/www/html/pdf/vendor/gears/pdf/src/Pdf.php on line 208