Use of undefined constant

[SCH_001]

I guess I am seeking some education on programming here on how to reduce the warnings in my error log
in the error logs I get
Use of undefined constant payright - assumed 'payright' (this will throw an Error in a future version of PHP) in /home/storename/public_html/store/payright.php on line 23

Line 23 reads   <h1 class="h3"><?php echo payright; ?></h1>

 

<?php
/*
  $Id$

  osCommerce, Open Source E-Commerce Solutions
  http://www.oscommerce.com

  Copyright (c) 2010 osCommerce

  Released under the GNU General Public License
*/

  require('includes/application_top.php');

  require('includes/languages/' . $language . '/payright.php');

  $breadcrumb->add(NAVBAR_TITLE, tep_href_link('payright.php'));

  require('includes/template_top.php');
?>
<!--
<div class="page-header">
  <h1 class="h3"><?php echo payright; ?></h1>
</div>
-->
<div class="contentContainer">
  <div class="contentText">

<!--    <?php echo TEXT_INFORMATION; ?> -->
 <iframe src="payright.html" style="border: none; width: 100%; height: 900px;"></iframe>

</div>
  <div class="buttonSet">
    <div class="text-right"><?php echo tep_draw_button(IMAGE_BUTTON_CONTINUE, 'fa fa-angle-right', tep_href_link('index.php')); ?></div>
  </div>
</div>

<?php
  require('includes/template_bottom.php');
  require('includes/application_bottom.php');
?>

 

[pandrei]

3 hours ago, SCH_001 said:

Line 23 reads   <h1 class="h3"><?php echo payright; ?></h1>

  <h1 class="h3"><?php echo ($payright ?? null); ?></h1>

 

[SCH_001]

1 hour ago, pandrei said:

  <h1 class="h3"><?php echo ($payright ?? null); ?></h1>

 

Thank you that resolved the issue. I will see what else I can apply this coding change to