What's causing an infinite loop?

I have to use parent posts as categories.

So I'm checking if current post has childs and show them or else show te content.

I'm trying like this (in single-practice.php):

?php
$has_children = false;
$children = get_children(
    array(
        'post_parent' = get_the_ID()
    )
);
wp_reset_postdata();
if ( ! empty($children) ) {
    $has_children = true;
}

if ($has_children) {

    $args = array(
        'post_type' = 'practice',
        'orderby' = 'menu_order',
        'post_parent' = get_the_ID(),
        'paged' = false
    );
    $query = new WP_Query( $args );
    /* var_dump($query); */

    ?
    div class="services"
        div data-isotope-options='{"itemSelector" : ".item","layoutMode" : "masonry","transitionDuration":"0.7s","masonry" : {"columnWidth":".item"}}' class="grid isotope clearfix portfolio-holder" 

        ?php while ( $query-have_posts() ) : $query-the_post();

        ?      
        div class="item item-col col-1 "
            a href="?php the_permalink(); ?" class="service-item"
                span class="overlay"/span
                figureimg width="320" height="305" src="?php echo wp_get_attachment_image_url(get_post_thumbnail_id(get_the_ID())); ?" class="attachment-320x305-center-center size-320x305-center-center wp-post-image" alt="" //figure
                span class="service-title"?php the_title(); ?/span
            /a
        /div
        ?php

        endwhile;
        wp_reset_postdata();
    ?/div
    /div!--/ .entry-box--?php 

} else {
    /* this is the original template code. */
    while ( have_posts() ) : the_post();

        get_template_part( 'template-parts/post/content', get_post_format() );

    endwhile;

    the_posts_pagination( array(
        'prev_text' = 'span class="screen-reader-text"' . esc_html__( 'Previous page', 'hickshynson' ) . '/span',
        'next_text' = 'span class="screen-reader-text"' . esc_html__( 'Next page', 'hickshynson' ) . '/span',
        'before_page_number' = 'span class="meta-nav screen-reader-text"' . esc_html__( 'Page', 'hickshynson' ) . ' /span'
    ) );


    the_content();

    wp_link_pages( array(
        'before'      = 'div class="page-links"' . esc_html__( 'Pages:', 'hickshynson' ),
        'after'       = '/div',
        'link_before' = 'span class="page-number"',
        'link_after'  = '/span',
    ) );
}
?

Note that the else is the same code that was in the template before I added the if.

For some reason, this code never finishes if the current post does not have children.. so I cannot see the page fully loaded,

What might be causing this? I'm using wp_reset_postadata() but the infinite loop still there,

Any idea?

-this is the $args how registered the post type-

$args = array(
    'labels' = hh_get_labels(
        __( 'Area', 'hh_app_textdomain' ),
        __( 'Areas', 'hh_app_textdomain' )
    ),
    'public' = true,
    'archive' = true,
    'exclude_from_search' = false,
    'publicly_queryable' = true,
    'show_ui' = true,
    'query_var' = true,
    'capability_type' = 'post',
    'has_archive' = true,
    'hierarchical' = true,
    'menu_position' = null,
    'supports' = array( 'title', 'editor', 'thumbnail', 'excerpt', 'page-attributes' ),
    'rewrite' = array( 'slug' = self::$slug ),
    'show_in_admin_bar' = true,
    'taxonomies' = array('post_tag'),
    'menu_icon' = 'dashicons-portfolio'
);

-UPDATE-

By removing this block

/* this is the original template code. */
while ( have_posts() ) : the_post();
    get_template_part( 'template-parts/post/content', get_post_format() );
endwhile;

The problem is no longer there. That's ok because the_content() has all I need, but still curious. Any thoughts?