Activate infinite scroll in custom template

I have done a lot of research… now I hope someone will help me.

I noticed that it was possible to activate the infinite scroll in a page (https://www.ads-software.com/support/topic/infinite-scroll-with-custom-post-types?replies=23) thanks to this snippet :

function my_load_infinite_scroll( $load_infinite_scroll ) {
    if( is_page('pagename') )
        return true;
    return $load_infinite_scroll;
}
add_filter('infinite_scroll_load_override', 'my_load_infinite_scroll');

Unfortunatly it doesn’t work for me…
I’m using a custom template for my page with a custom query. Any ideas ?

https://www.ads-software.com/extend/plugins/infinite-scroll/