ACF repeater inside group

Question

I tried to get ACF repeater from the group field. I must be blind, but I cannot find a mistake inside my code.

<?php if( have_rows( 'acf_group' ) ): ?>
    
    <?php while( have_rows( 'acf_group' ) ): the_row(); ?>

        <?php if( have_rows( 'acf_repeater' ) ): ?>
    
        <ul>
    
            <?php while( have_rows( 'acf_repeater' ) ): the_row();
                
                $link_text = get_sub_field( 'acf_repeater_field_text' );
                $link_url = get_sub_field( 'acf_repeater_field_url' );
            ?>
    
            <li>
                <a href="<?php echo $link_url; ?>"><?php echo $link_text; ?></a>
            </li>

            <?php endwhile; ?>
            
        </ul>

        <?php endif; ?>

    <?php endwhile; ?>

<?php endif; ?>