Warning: fopen(counter.txt): Failed to open stream: Permission denied in /var/www/html/index.php on line 22

Fatal error: Uncaught TypeError: fwrite(): Argument #1 ($stream) must be of type resource, false given in /var/www/html/index.php:23 Stack trace: #0 /var/www/html/index.php(23): fwrite() #1 {main} thrown in /var/www/html/index.php on line 23