diff --git a/includes/admin/class-wc-admin-duplicate-product.php b/includes/admin/class-wc-admin-duplicate-product.php
index c8514c0e5a0..4bfa4aeb1e7 100644
--- a/includes/admin/class-wc-admin-duplicate-product.php
+++ b/includes/admin/class-wc-admin-duplicate-product.php
@@ -221,6 +221,7 @@ class WC_Admin_Duplicate_Product {
 		$post_meta_infos = $wpdb->get_results("SELECT meta_key, meta_value FROM $wpdb->postmeta WHERE post_id=$id");
 
 		if (count($post_meta_infos)!=0) {
+			$sql_query_sel = array();
 			$sql_query = "INSERT INTO $wpdb->postmeta (post_id, meta_key, meta_value) ";
 			foreach ($post_meta_infos as $meta_info) {
 				$meta_key = $meta_info->meta_key;