> For the complete documentation index, see [llms.txt](https://wallee.gitbook.io/documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wallee.gitbook.io/documentation/payments/integrations/features/fraud-prevention.md).

# Fraud Prevention

Fraud prevention protects you from accepting payments that are later reversed — through a stolen card, an unauthorized transaction or a chargeback. In an omnichannel setup, the risk exists both online and in store, so {inject-platform-name} combines several mechanisms rather than a single switch.

This page brings those mechanisms together. Each is documented in detail on its own page; use this page to understand how they fit into one line of defence.

### The layers of protection

| Layer                                                                                                                       | Protects against                                                                               | Channel             |
| --------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------- | ------------------- |
| [3-D Secure](/documentation/payments/integrations/features/3-d-secure.md)                                                   | Unauthorized use of a card in online payments; shifts chargeback liability to the card issuer. | Online cards        |
| [Manual Tasks](/documentation/readme/manual-tasks.md)                                                                       | Suspicious transactions that need a human decision before you deliver.                         | Online and in store |
| [Delivery indications](/documentation/payments/overview/transaction-states/delivery-indications.md) and the `Decline` state | Delivering goods for a payment that carries a high chargeback risk.                            | Online and in store |

### How the layers work together

**Before the payment — 3-D Secure.** For online card payments, [3-D Secure](/documentation/payments/integrations/features/3-d-secure.md) authenticates the cardholder with the card issuer. A successful authentication shifts the liability for a fraudulent chargeback from you to the issuer. You configure it per payment method, and you can make it conditional on properties such as the transaction amount or the country.

**During processing — a decision when something looks wrong.** When a transaction is flagged as suspicious, the platform does not silently accept or reject it: it creates a [manual task](/documentation/readme/manual-tasks.md) so a person decides how to proceed. Each manual task has an expiry, and if you do not respond in time a default decision is applied based on who carries the risk.

**Before fulfillment — the delivery decision.** A transaction only reaches the `Fulfill` state once it is safe to deliver. If the risk of a chargeback is too high, it moves to the `Decline` state instead, and you must not fulfill the order. See [Transaction States](/documentation/payments/overview/transaction-states.md) and [Delivery indications](/documentation/payments/overview/transaction-states/delivery-indications.md).

{% hint style="info" %}
These layers reinforce each other. 3-D Secure reduces how often a payment becomes suspicious in the first place; manual tasks catch the cases that still need judgment; the delivery decision is the final gate before you part with the goods.
{% endhint %}

### What to do when you suspect fraud

* **Do not fulfill the order** while the transaction is still being reviewed — a transaction in the `Decline` state must not be delivered.
* **Check your open manual tasks** — a suspicious transaction usually surfaces there and waits for your decision.
* **Review the authorisation response** for a declined card payment — see [Authorisation Response](/documentation/payments/overview/transaction-states/authorisation-response.md) for the response codes.

### Related topics

* [3-D Secure](/documentation/payments/integrations/features/3-d-secure.md) — cardholder authentication and the liability shift.
* [Manual Tasks](/documentation/readme/manual-tasks.md) — how the platform asks for your decision on a suspicious transaction.
* [Transaction States](/documentation/payments/overview/transaction-states.md) — the `Decline` and `Fulfill` states that end a risky transaction.
* [PCI DSS](/documentation/payments/overview/transaction-states/pci-dss.md) — how card data is protected throughout the payment.