diff --git a/addons/website_sale/static/src/js/website_sale_options.js b/addons/website_sale/static/src/js/website_sale_options.js
index ab3542589af..c0adc909bce 100644
--- a/addons/website_sale/static/src/js/website_sale_options.js
+++ b/addons/website_sale/static/src/js/website_sale_options.js
@@ -131,7 +131,7 @@ sAnimations.registry.WebsiteSaleOptions = sAnimations.Class.extend(ProductConfig
      */
     _onOptionsUpdateQuantity: function (quantity) {
         this.$form
-            .find('input[name="add_qty"]')
+            .find('.js_main_product input[name="add_qty"]')
             .first()
             .val(quantity)
             .trigger('change');