Code works in Child Theme, but not WPCode

The following code aligns the last modified date with the published date. It works in a child theme but does not work in WPCode. Does anyone know why?

<?php

// Hook into the 'the_modified_date' filter for posts
add_filter( 'the_modified_date', 'wpse_modified_date', 10, 2 );

// Hook into the 'the_time' filter for pages
add_filter( 'the_time', 'wpse_modified_date', 10, 2 );

/**
 * Replace the published date with the last modified date.
 *
 * @param string  $the_modified_date   The current date string.
 * @param string  $date_format The date format.
 * @return string The modified date string.
 */
function wpse_modified_date( $the_modified_date, $date_format ) {
	// Get the post object
	$post = get_post();

	// Get the last modified date
	$modified_date = get_the_modified_date( $date_format, $post );

	// Replace the published date with the modified date
	return $modified_date;
}

?>