When you run the SSL install form of WP Encryption, you might notice “parse error reading JWS” error in the debug log. WP Encryption plugin not being able to create keys/ directory due to file permission issues could lead to this error.
Please login to your SSH console as root / sudo user, cd into your WordPress directory and update the owner group of directory recursively to allow apache / www-data user to create directory within WordPress. You can do so via below command,
sudo chown -R www-data:www-data /var/www/html
Please make sure to replace /var/www/html to your WordPress site folder path.