Just found the error message in the email, which will hopefully be helpful:
Error Details
=============
An error of type E_ERROR was caused in line 698 of the file /home3/dsbwzhmy/public_html/wp-content/plugins/court-reservation/admin/partials/courtres-settings.php. Error message: Uncaught TypeError: in_array(): Argument #2 ($haystack) must be of type array, bool given in /home3/dsbwzhmy/public_html/wp-content/plugins/court-reservation/admin/partials/courtres-settings.php:698
Stack trace:
#0 /home3/dsbwzhmy/public_html/wp-content/plugins/court-reservation/admin/partials/courtres-settings.php(698): in_array('Single', false)
#1 /home3/dsbwzhmy/public_html/wp-content/plugins/court-reservation/admin/class-courtres-admin.php(703): require_once('/home3/dsbwzhmy...')
#2 /home3/dsbwzhmy/public_html/wp-includes/class-wp-hook.php(307): Courtres_Admin->load_admin_settings('')
#3 /home3/dsbwzhmy/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters('', Array)
#4 /home3/dsbwzhmy/public_html/wp-includes/plugin.php(476): WP_Hook->do_action(Array)
#5 /home3/dsbwzhmy/public_html/wp-admin/admin.php(259): do_action('toplevel_page_c...')
#6 {main}
thrown