{"section":"faq","requestedLocale":"en","requestedSlug":"why-was-the-user-id-requested-at-checkout-when-the-purchase-was-concluded","locale":"en","slug":"why-was-the-user-id-requested-at-checkout-when-the-purchase-was-concluded","path":"docs/en/faq/checkout/why-was-the-user-id-requested-at-checkout-when-the-purchase-was-concluded.md","branch":"main","content":"Checkout applies a security rule to SmartCheckout purchases.\n\nReturning customers can complete a SmartCheckout purchase with only their email address and card CVV. After three unsuccessful attempts, checkout asks the customer to log in.\n\n![LoginEN](https://cdn.statically.io/gh/vtexdocs/help-center-content/refs/heads/main/docs/en/faq/checkout/why-was-the-user-id-requested-at-checkout-when-the-purchase-was-concluded_1.png)\n\nIf three consecutive attempts with email and CVV are not approved by the card operator, a login screen is displayed so the customer can keep trying. The counter resets after the customer logs in and completes a purchase.\n\n> ⚠️ A new login is required only after three unsuccessful attempts with the same card. The time between attempts does not matter. After the third failed attempt, checkout asks the customer to authenticate.\n\nThis protects customer data against attacks and fraud.\n\nFor more information, see [SmartCheckout Security](/en/docs/tutorials/smartcheckout-security)."}