AJAX warnings

Hi,
We are trying to figure out if there is a problem caused by your plugin. (Occasionally, our website goes offline with a 503 error code and we are not sure why. We installed Query Monitor to help us find the trouble)

The following AJAX warning were noted by Query Monitor:

Objectcomponent: “Plugin: woo-product-category-discount-pro”file: “wp-content/plugins/woo-product-category-discount-pro/cd-admin.php”key: “bd44520504fbcad575f9d8ec664766da”line: 841message: “array_unique() expects parameter 1 to be array, null given”stack: (11)?[“array_unique()”, “wpcdp_save_product_discount()”, “do_action(‘save_post_product’)”, “wp_insert_post()”, “wp_update_post()”, “edit_post()”, “wp_autosave()”, “heartbeat_autosave()”, “apply_filters(‘heartbeat_received’)”, “wp_ajax_heartbeat()”, “do_action(‘wp_ajax_heartbeat’)”]type: “warning”__proto__: Object
(anonymous) @ query-monitor.js?ver=1612278631:376
query-monitor.js?ver=1612278631:376 Objectcomponent: “Plugin: woo-product-category-discount-pro”file: “wp-content/plugins/woo-product-category-discount-pro/cd-admin.php”key: “e5fdcda313e1a206d691661197cd951a”line: 841message: “implode(): Invalid arguments passed”stack: (11)?[“implode()”, “wpcdp_save_product_discount()”, “do_action(‘save_post_product’)”, “wp_insert_post()”, “wp_update_post()”, “edit_post()”, “wp_autosave()”, “heartbeat_autosave()”, “apply_filters(‘heartbeat_received’)”, “wp_ajax_heartbeat()”, “do_action(‘wp_ajax_heartbeat’)”]type: “warning”__proto__: Object
(anonymous) @ query-monitor.js?ver=1612278631:376
query-monitor.js?ver=1612278631:376 Objectcomponent: “Plugin: woo-product-category-discount-pro”file: “wp-content/plugins/woo-product-category-discount-pro/cd-admin.php”key: “3cdc75d33edf14e72fcc530ee110d099″line: 662message: “in_array() expects parameter 2 to be array, null given”stack: (12)?[“in_array()”, “wpcdp_get_discount_amount()”, “wpcdp_save_product_discount()”, “do_action(‘save_post_product’)”, “wp_insert_post()”, “wp_update_post()”, “edit_post()”, “wp_autosave()”, “heartbeat_autosave()”, “apply_filters(‘heartbeat_received’)”, “wp_ajax_heartbeat()”, “do_action(‘wp_ajax_heartbeat’)”]type: “warning”__proto__: Object
(anonymous) @ query-monitor.js?ver=1612278631:376

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