PHP Fileinfo extension must be installed/enabled at shared hosting

"PHP Fileinfo extension must be installed/enabled to use Intervention Image " showing this error message when I upload image on my shared hosting. So, I modified my php.ini file using .htaccess file.

Now my .htaccess file looks like,

<IfModule mod_rewrite.c>
    <IfModule mod_negotiation.c>
        Options -MultiViews
    </IfModule>

    RewriteEngine On

    # Redirect Trailing Slashes...
    RewriteRule ^(.*)/$ /$1 [L,R=301]

    # Handle Front Controller...
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.php [L]

<IfModule mod_suphp.c>
suPHP_ConfigPath /home/username/public_html/subfolder
</IfModule>

</IfModule>

subfolder is the laravel project where I want to serve my application.

php.ini file in my subfolder's root folder & for enable PHPFileinfo I write those code in php.ini file

extension=fileinfo.so
extension=pdo.so
extension=pdo_mysql.so

And finally it doesn't work in my shared hosting!! :(

How can I solve it?