Undefined Arrays after WP upgrade

After updating to WP 5.8.2, these warnings appear on the Events page:

Warning: Undefined array key "filters" in /home/geekfreepc/public_html/theplacerentalhall/wp/wp-content/plugins/event-calendar-wd/includes/ecwd-shortcodes.php on line 64

Warning: Undefined array key "page_items" in /home/geekfreepc/public_html/theplacerentalhall/wp/wp-content/plugins/event-calendar-wd/includes/ecwd-shortcodes.php on line 64

Warning: Undefined array key "event_search" in /home/geekfreepc/public_html/theplacerentalhall/wp/wp-content/plugins/event-calendar-wd/includes/ecwd-shortcodes.php on line 64

My theme is Herschel

The page I need help with: [log in to see the link]