I see this a bunch of times, and can't figure out what causes it. The IP address is always registered to PayPal.

Code:
[02-Dec-2023 13:47:12 America/Los_Angeles] Request URI: /store/ipn_main_handler.php, IP address: 173.0.81.65, Language id 1
#1  trigger_error() called at [/home/domain/public_html/store/includes/classes/db/mysql/query_factory.php:667]
#2  queryFactory->show_error() called at [/home/domain/public_html/store/includes/classes/db/mysql/query_factory.php:634]
#3  queryFactory->set_error() called at [/home/domain/public_html/store/includes/classes/db/mysql/query_factory.php:275]
#4  queryFactory->Execute() called at [/home/domain/public_html/store/includes/modules/shipping/freeoptions.php:104]
#5  freeoptions->update_status() called at [/home/domain/public_html/store/includes/modules/shipping/freeoptions.php:85]
#6  freeoptions->__construct() called at [/home/domain/public_html/store/includes/classes/shipping.php:91]
#7  shipping->__construct() called at [/home/domain/public_html/store/ipn_main_handler.php:318]
--> PHP Fatal error: 1064:You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'ORDER BY zone_id' at line 5 :: SELECT zone_id
                   FROM zen_zones_to_geo_zones
                  WHERE geo_zone_id = 2
                    AND zone_country_id = 
                  ORDER BY zone_id ==> (as called by) /home/domain/public_html/store/includes/modules/shipping/freeoptions.php on line 104 <== in /home/domain/public_html/store/includes/classes/db/mysql/query_factory.php on line 667.