Critical error on WordPress RSVPMaker template

I have many orphan RSVPMaker Events that have been deleted but still show up on your listing of events. Error is:


An error of type E_ERROR was caused in line 49 of the file /home/johmur48/couplesclubofrossmoor.com/wp-content/plugins/rsvpmaker/rsvpmaker-util.php. Error message: Uncaught Error: Call to a member function get_var() on null in /home/johmur48/couplesclubofrossmoor.com/wp-content/plugins/rsvpmaker/rsvpmaker-util.php:49
Stack trace:

0 /home/johmur48/couplesclubofrossmoor.com/wp-content/plugins/rsvpmaker/rsvpmaker.php(788): add_rsvpmaker_event(9028, '2023-05-11 00:0…', '1969-12-31 17:0…', 'allday')

1 /home/johmur48/couplesclubofrossmoor.com/wp-content/plugins/rsvpmaker/rsvpmaker-admin.php(3437): add_rsvpmaker_date(9028, '2023-05-11 00:0…', 'allday')

2 /home/johmur48/couplesclubofrossmoor.com/wp-includes/class-wp-hook.php(308): rsvpmaker_template_checkbox_post('')

3 /home/johmur48/couplesclubofrossmoor.com/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)

4 /home/johmur48/couplesclubofrossmoor.com/wp-includes/plugin.php(517): WP_Hook->do_action(Array)

5 /home/johmur48/couplesclubofrossmoor.com/wp-admin/admin.php(175): do_action('admin_init')

6 /home/johmur48/couplesclubofrossmoor.com/wp-admin/edit.php(10): require_once('/home/johmur48/…')

7 {main}

thrown

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