Custom Part Search Box just disappeared

Hi there!

I am trying to figure out why my search box just disappeared in the last 2 months. It was working like a charm for over 2 years, but now it has vanished.

My searchform.php file looks like this:

<form role="search" method="post" class="searchform" action="https://www.calportaviation.com/search-results/">
    <div><label class="screen-reader-text" for="term">Search for:</label>
        <input type="search" value="" placeholder="Part Number or NSN" name="term" id="term" />
        <input type="submit" id="searchsubmit" value="Search" />
    </div>
</form>

And my search-results.php file looks like this:

<?php
/* Template Name: Search Results
*/
get_header();
?>

<section id="primary" class="content-area">
	<main id="main" class="site-main" role="main">
	
			<?php

global $wpdb;

$PartNum = $_POST['term'];
$PartNum = sanitize_text_field( $_POST['term'] );
update_post_meta( $post->ID, 'term', $PartNum );

$query_Parts = $wpdb->get_results( "SELECT * FROM parts WHERE parts.PartNumber LIKE '%$PartNum%' or parts.nsn LIKE '%$PartNum%'");
		
		if ( ! empty( $query_Parts ) ) : ?>

			<header class="page-header">
				<h1 class="page-title"><?php printf(__( 'Search Results for: %s', 'catalog-me' ), '<span>' . $_POST['term'] . '</span>' ); ?></h1>
			</header><!-- .page-header -->

			<?php

			//echo "<pre>"; print_r($query_Parts); echo "</pre>";

echo '<table class="results"><thead><tr><th>Part Number</th><th>NSN</th><th>Alternate Part Number</th><th>Description</th><th>Condition</th><th>Quantity</th></tr></thead><tbody>';

foreach($query_Parts as $row) {
echo '<tr>';
echo "<td>{$row->PartNumber}</td>";
echo "<td>{$row->nsn}</td>";
echo "<td>{$row->nsn2}</td>";
echo "<td>{$row->Description}</td>";
echo "<td>{$row->Condition}</td>";
echo "<td>{$row->CVQuantity}</td>"; 
echo '</tr>';
}

echo '</tbody></table>';
		?>

		<?php else : ?>
		
<h2 class="center">P/N: <?php echo $PartNum; ?> Not Found</h2>
<p class="center">Sorry, it doesn't look like we have Part Number <?php echo $PartNum; ?> in our Inventory database.  Try a new search with Alternate Part Number or NSN.</p>
	
		<?php endif; ?>

	</main><!-- #main -->
</section><!-- #primary -->
</div>
<?php
get_footer();

It has been so long that I have had to work on any coding so I am having trouble trying to figure out where to start to fix it!

Any help would be greatly appreciated. Thank you!

-Amy

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