add fizzly on images not in content

Hello,
I’m calling thumbnails with featured image before content and title with:

if ( has_post_thumbnail() ) {
			the_post_thumbnail( 'full');
		}

Fizzy do not work on this image and I tried to add a class like

if ( has_post_thumbnail() ) {
			the_post_thumbnail( 'full',  array( 'class' => 'frizzly-image-hover') );
		}

but it’s not enough. Have you some idea to solve it ?

https://www.ads-software.com/plugins/frizzly/