My repeater fields actually work fine, but the first one is not showing up.
I am not that much into PHP, but here is the code, maybe somebody could identify an issue. Thanks in advance:
<?php if(has_sub_field('speakers')) { ?>
<div class="speakers-list clearfix">
<h2>REFERENTEN:</h2>
<?php while(has_sub_field('speakers')){ ?>
<div class="speaker">
<div class="speaker-image">
<?php if (get_sub_field('image')[url]) { ?>
<img src="<?php echo get_sub_field('image')[url]; ?>" ?>
<?php } else { ?>
<?php echo get_avatar( 'email@example.com', 32 ); ?>
<?php } ?>
</div>
<div class="speaker-content">
<h3><span><?php echo get_sub_field('first_name'); ?></span><?php echo get_sub_field('last_name'); ?></h3>
<div class="speaker-company"><?php echo get_sub_field('company'); ?></div>
<div class="speaker-role"><?php echo get_sub_field('role'); ?></div>
<div class="speaker-social">
<ul class="list-inline">
<?php if (get_sub_field('website') != '') : ?>
<li><a href="<?php echo http_check(get_sub_field('website')); ?>" target="_blank"><i class="fa fa-globe fa-lg"></i></a></li>
<?php endif; ?>
</ul>
</div>
</div>
</div>
<?php } ?>
</div>
<?php } ?>
Solved it on my own 
First line:
<?php if(have_rows('speakers')) { ?>
