New error with get_queried_object()

Since yesterday, I’ve been getting a PHP error from the simple-tags plugin – see below. Could you help please.

[02-Jun-2021 05:20:17 UTC] PHP Fatal error Uncaught Error: Call to a member function get_queried_object() on null in /home/customer/www/seascamp.org.uk/public_html/wp-includes/query.php:44

Stack trace:

#0 /home/customer/www/seascamp.org.uk/public_html/wp-content/plugins/simple-tags/inc/class.client.php(73): get_queried_object()
#1 /home/customer/www/seascamp.org.uk/public_html/wp-includes/class-wp-hook.php(292): SimpleTags_Client::cpt_taxonomy_parse_query(Object(WP_Query))
#2 /home/customer/www/seascamp.org.uk/public_html/wp-includes/class-wp-hook.php(316): WP_Hook->apply_filters('', Array)
#3 /home/customer/www/seascamp.org.uk/public_html/wp-includes/plugin.php(551): WP_Hook->do_action(Array)
#4 /home/customer/www/seascamp.org.uk/public_html/wp-includes/class-wp-query.php(1083): do_action_ref_array('parse_query', Array)
#5 /home/customer/www/seascamp.org.uk/public_html/wp-includes/class-wp-query.php(1771): WP_Query->parse_query()
#6 /home/customer/www/seascamp.org.uk/public_html/wp-includes/class-wp-query.php(3465): WP_Query->get_posts()
#7 /home/cus in /home/customer/www/seascamp.org.uk/public_html/wp-includes/query.php on line 44

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