comment_form

I’m using the Underscores theme(by Automattic) with a custom post type with comments enabled. The comments form is showing up.. but without the opening and closing <form> tags. The form fields are there.. as well as the submit button.. but no actual form tag.
The comments.php is still default. The command is the default comment_form(); without any options. Any idea where to start looking for what is wrong?

<div id="comments" class="comments-area">
	<div id="respond">
		<h3 id="reply-title">Leave a Reply <small><a rel="nofollow" id="cancel-comment-reply-link" href="/case/patient-1521/#respond" style="display:none;">Cancel reply</a></small></h3>

		<p class="logged-in-as">Logged in as <a href="https://digitalsmilelab.com/wp-admin/profile.php">Matthew</a>. <a href="https://digitalsmilelab.com/logout/?_wpnonce=61f100e60b" title="Log out of this account">Log out?</a></p>
		<p class="comment-form-comment"><label for="comment">Comment</label><textarea id="comment" name="comment" cols="45" rows="8" aria-required="true"></textarea></p>
		<p class="form-allowed-tags">You may use these <abbr title="HyperText Markup Language">HTML</abbr> tags and attributes:  <code><a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong> </code></p>
		<p class="form-submit">
			<input name="submit" type="submit" id="submit" value="Post Comment">
			<input type="hidden" name="comment_post_ID" value="1521" id="comment_post_ID">
			<input type="hidden" name="comment_parent" id="comment_parent" value="0">
		</p>
			<input type="hidden" id="_wp_unfiltered_html_comment_disabled" name="_wp_unfiltered_html_comment" value="8eb533c9ea">
			<script>
				(function(){if(window===window.parent){document.getElementById('_wp_unfiltered_html_comment_disabled').name='_wp_unfiltered_html_comment';}})();
			</script>
	</div><!-- #respond -->
</div>