<div class="error-block">
    <h2>Import errors</h2>
    <div class="error-accordion">
        <?php foreach(\Session::get('error_data') as $error_line): ?>
            <div class="collapse">
            <h3>Product: <?php echo $error_line['reference']; ?></h3>
                <ul class="collapsible-ul">
                    <?php foreach($error_line['errors'] as $error): ?>
                        <li><?php echo $error; ?></li>
                    <?php endforeach; ?>
                </ul>
            </div>
        <?php endforeach; ?>
    </div>
</div>