Solved - Inserting content inside the WordPress loop

I currently trying to insert a block of custom code inside the WordPress posts loop which is using JetPack's infinite scroll functionality. In theory, this should be quite simple but is proving otherwise.

this is what I have currently written:

    ?php
        $count = 0;
        while( have_posts() ) :
            the_post();

            get_template_part( 'content-post', get_post_format() );
            if ($count === 4) {
                get_template_part( 'block-one', get_post_format() );
            }

            $count ++;
        endwhile;
    ?

So, if the count is at 4 insert the custom block. However, when I look at my homepage, I get this view:

The custom code block has been added before the posts. I can't quite find out why.

Any suggestions?

EDIT:

Here is the content.php:

a class="post-container-home" href="?php the_permalink() ?"
    div
        class="post-image"
        style="background: url(?php the_post_thumbnail_url() ?)"
    
    /div
    div class="post-info-home"
        h3Test/h3
        pTitle/p
        div class="post-time"
            h3min read/h3
        /div
    /div
/a

Here is block-one.php:

div id="newsletter" class="post-container-home"
    img src="/theme-new/wp-content/themes/theme-blog-new/img/subscribe.png" alt="subscribe"
/div

Thanks,