acf repeat in repeat

gistfile1.txt

// check if the repeater field has rows of data
if( have_rows('erkenningen') ):
 	// loop through the rows of data
    while ( have_rows('erkenningen') ) : the_row(); ?>
        <div class="ersegment row">
				<div class="small-12 large-12 medium-6 columns">
				<h3><?php the_sub_field('titel_erkenningen'); ?></h3>
				
				<?php while ( have_rows('soorten_erkenning_categorie') ) : the_row(); ?>
				<ul class='erkenninglist'>
				<li class='w30'><?php  the_sub_field('categorie'); ?></li>
				<li class='w70'><?php  the_sub_field('omschrijving'); ?></li>
				</ul>
				<?php endwhile; ?>

				</div>
			
			</div>
	<?php
    endwhile;
else :
    // no rows found
endif;
?>