Getting E_ERROR. Please fix ASAP!

Just installed your plugin but I get this massive error. What’s the cause of this? Can you please fix ASAP?

WordPress version 5.4.2
Current theme: Wicky (version 1.0.1)
Current plugin: Woocommerce Multi Warehouses (version 1.3.6)
PHP version 7.3.18
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An error of type E_ERROR was caused in line 673 of the file /srv/htdocs/wp-content/plugins/warehouse-popups-woocommerce/public/class-warehouse-popups-woocommerce-public.php. Error message: Uncaught Error: Undefined class constant ‘client_data’ in /srv/htdocs/wp-content/plugins/warehouse-popups-woocommerce/public/class-warehouse-popups-woocommerce-public.php:673
Stack trace:
#0 /wordpress/core/5.4.2/wp-includes/class-wp-hook.php(287): Warehouse_Popups_Woocommerce_Public->wh_popups_override_currency(‘IDR’)
#1 /wordpress/core/5.4.2/wp-includes/plugin.php(206): WP_Hook->apply_filters(‘IDR’, Array)
#2 /wordpress/plugins/woocommerce/4.2.0/includes/wc-core-functions.php(319): apply_filters(‘woocommerce_cur…’, ‘IDR’)
#3 /wordpress/plugins/woocommerce/4.2.0/includes/wc-core-functions.php(701): get_woocommerce_currency()
#4 /wordpress/plugins/woocommerce/4.2.0/includes/widgets/class-wc-widget-price-filter.php(45): get_woocommerce_currency_symbol()
#5 /wordpress/core/5.4.2/wp-includes/class-wp-widget-factory.php(61): WC_Widget_Price_Filter->__construct()
#6 /wordpress/core/5.4.2/wp-includes/widgets.php(115): WP_Widget_Factory->register(‘WC_Widget_Price…’)
#7 /wordpress/plugins/woocommerce/4.2.0/includes/wc-widget-functions.php(39): register_widget(‘WC_Widget_Price…’)
#8 /wordpress/core/5.4.2/wp-includes/class-wp-hook.php(287): wc_register_widgets(”)
#9 /wordpress/core/5.4.2/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#10 /wordpress/core/5.4.2/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#11 /wordpress/core/5.4.2/wp-includes/widgets.php(1765): do_action(‘widgets_init’)
#12 /wordpress/core/5.4.2/wp-includes/class-wp-hook.php(287): wp_widgets_init(”)
#13 /wordpress/core/5.4.2/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#14 /wordpress/core/5.4.2/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#15 /wordpress/core/5.4.2/wp-settings.php(540): do_action(‘init’)
#16 /srv/htdocs/wp-config.php(81): require_once(‘/wordpress/core…’)
#17 /wordpress/core/5.4.2/wp-load.php(42): require_once(‘/srv/htdocs/wp-…’)
#18 /wordpress/core/5.4.2/wp-login.php(12): require(‘/wordpress/core…’)
#19 {main}
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