PHP 8 custom theme update error

After updating site to php and WP 8 I get this warning

Warning: Attempt to read property "cat_ID" on null and it’s coming from functions.php

here is the block of code:

add_action('pre_get_posts', 'pre_get_posts_mod1' ); 
	function pre_get_posts_mod1( $wp_query ) { 
 
	$excluded =  get_resource_cat_ids();  
 	//exclude podcast category by ID 
	array_push($excluded, '9', '1691'); 
	  
	$page_object = get_queried_object(); 
	$cat_ID = $page_object->cat_ID; 
	//do we exclude anything from main loop? 
	if (!in_array( $cat_ID , $excluded )) {
	//exclude categories
	set_query_var('category__not_in', $excluded);  
		}	  
	
 }

Stack trace from debug log

[10-Jun-2022 13:18:20 UTC] PHP Stack trace:
[10-Jun-2022 13:18:20 UTC] PHP   1. {main}() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-admin/admin-ajax.php:0
[10-Jun-2022 13:18:20 UTC] PHP   2. require_once() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-admin/admin-ajax.php:22
[10-Jun-2022 13:18:20 UTC] PHP   3. require_once() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-load.php:50
[10-Jun-2022 13:18:20 UTC] PHP   4. require_once() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-config.php:92
[10-Jun-2022 13:18:20 UTC] PHP   5. do_action() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-settings.php:620
[10-Jun-2022 13:18:20 UTC] PHP   6. WP_Hook->do_action() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/plugin.php:476
[10-Jun-2022 13:18:20 UTC] PHP   7. WP_Hook->apply_filters() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-hook.php:331
[10-Jun-2022 13:18:20 UTC] PHP   8. wpDiscuzForm->initPersonalDataExporter() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-hook.php:307
[10-Jun-2022 13:18:20 UTC] PHP   9. wpdFormAttr\Tools\PersonalDataExporter::getInstance() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-content/plugins/wpdiscuz/forms/wpDiscuzForm.php:60
[10-Jun-2022 13:18:20 UTC] PHP  10. wpdFormAttr\Tools\PersonalDataExporter->__construct() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-content/plugins/wpdiscuz/forms/wpdFormAttr/Tools/PersonalDataExporter.php:112
[10-Jun-2022 13:18:20 UTC] PHP  11. wpdFormAttr\Tools\PersonalDataExporter->initFormsFields() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-content/plugins/wpdiscuz/forms/wpdFormAttr/Tools/PersonalDataExporter.php:16
[10-Jun-2022 13:18:20 UTC] PHP  12. get_posts() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-content/plugins/wpdiscuz/forms/wpdFormAttr/Tools/PersonalDataExporter.php:21
[10-Jun-2022 13:18:20 UTC] PHP  13. WP_Query->query() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/post.php:2410
[10-Jun-2022 13:18:20 UTC] PHP  14. WP_Query->get_posts() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-query.php:3586
[10-Jun-2022 13:18:20 UTC] PHP  15. do_action_ref_array() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-query.php:1805
[10-Jun-2022 13:18:20 UTC] PHP  16. WP_Hook->do_action() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/plugin.php:524
[10-Jun-2022 13:18:20 UTC] PHP  17. WP_Hook->apply_filters() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-hook.php:331
[10-Jun-2022 13:18:20 UTC] PHP  18. pre_get_posts_mod1() /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-includes/class-wp-hook.php:307
[10-Jun-2022 13:18:20 UTC] PHP Warning:  Attempt to read property "cat_ID" on null in /Users/jasonsprague/Local Sites/marketsmart-site/app/public/wp-content/themes/imarketsmart/functions.php on line 242