Are you referring to the archive subtitle / description like in the screenshot below?

If so, you’ll need to override _landmark-header.php which is located in pro\framework\legacy\cranium\headers\views\integrity. In case you don’t know how to override templates in Pro yet, please see our theme customization guide at https://theme.co/apex/forum/t/customizations-best-practices/205
Find these lines of code:
<?php elseif ( x_is_product_category() ) : ?>
<?php elseif ( x_is_product_tag() ) : ?>
Below each of those lines, you’ll see this block of code:
<header class="x-header-landmark x-container max width">
<h1 class="h-landmark"><span><?php echo $title; ?></span></h1>
<p class="p-landmark-sub"><span><?php echo $subtitle; ?></span></p>
</header>
Remove all of that code or parts of it. Please note that this requires web developer knowledge. If you’re not familiar with web development, you need to enlist help from a third party developer.
If that is not the area you want to modify, please provide us the URL of the page and a screenshot of the area so we could provide the specific correct solution and avoid guess work.
Thanks.