> ## Documentation Index
> Fetch the complete documentation index at: https://support.wepayments.com.br/llms.txt
> Use this file to discover all available pages before exploring further.

# Approval Rate Optimization

This guide covers improving credit card approval rates, understanding the anti-fraud procedure, using free/block lists, the chargeback process, and restrictive lists.

## Anti-fraud procedure (Credit Card)

The anti-fraud system is provided by our card processing partner and applies exclusively to **Credit Card transactions**.

### How it works

| **Component**               | **Description**                                                      |
| :-------------------------- | :------------------------------------------------------------------- |
| **Neural network**          | Interconnects multiple databases with dynamic indexing rules         |
| **Machine learning engine** | Feeds risk analysis rule trees with behavioral pattern data          |
| **Rule trees**              | Map scenario-specific behavioral patterns to prevent false positives |

> 💡 The system is designed to ensure that false positives do not contaminate the analyses.

### Critical field: Email address

The **email address** is one of the most important fields for fraud checking. Incorrect email addresses can trigger false fraud alerts.

| **Best practice**                 | **Why**                                 |
| :-------------------------------- | :-------------------------------------- |
| Always fill email correctly       | Prevents unnecessary fraud flags        |
| Use business emails when possible | More reliable than free email providers |
| Verify email format               | Simple typos cause false positives      |

## Free and block lists

You can create custom lists to improve approval rates without compromising security.

| **List type**  | **Effect**                                                                                                            |
| :------------- | :-------------------------------------------------------------------------------------------------------------------- |
| **Free list**  | Releases buyers according to their consumption profile – transactions from these emails are less likely to be flagged |
| **Block list** | Blocks buyers based on risk profile – transactions from these emails are automatically rejected                       |

> 💡 Using free and block lists helps increase purchase approval rates for legitimate customers while maintaining security.

### How to use free/block lists

| **Step**                 | **Action**                                                    |
| :----------------------- | :------------------------------------------------------------ |
| **1. Identify patterns** | Analyze customer behavior to identify trusted and risky users |
| **2. Add to list**       | Configure lists via Dashboard or API                          |
| **3. Monitor**           | Track approval rates and adjust as needed                     |

## Restrictive lists and screening

WEpayments screens transactions against multiple restrictive lists:

| **List type**            | **Description**                                  |
| :----------------------- | :----------------------------------------------- |
| **Sanctions lists**      | OFAC, UN, EU, and Brazilian government sanctions |
| **PEP lists**            | Politically Exposed Persons                      |
| **Internal blacklists**  | Entities previously flagged                      |
| **Watchlists**           | Regulatory and law enforcement lists             |
| **Negative media lists** | Entities associated with adverse news            |

> 💡 Transactions involving entities on sanctions lists are automatically blocked.

## Understanding the credit card chargeback process

A **chargeback** occurs when a customer disputes a transaction with their card issuer and requests a refund.

### Common chargeback reasons

| **Reason**                   | **Description**                                           |
| :--------------------------- | :-------------------------------------------------------- |
| **Fraudulent transaction**   | Customer claims they did not authorize the purchase       |
| **Product not received**     | Customer claims they never received the product/service   |
| **Product not as described** | Customer claims product/service differed from description |
| **Technical error**          | Customer was charged multiple times or incorrect amount   |

### How to prevent chargebacks

| **Prevention measure**    | **Description**                                            |
| :------------------------ | :--------------------------------------------------------- |
| **Clear descriptors**     | Statement descriptor should clearly identify your business |
| **Shipping confirmation** | Provide tracking numbers and delivery proof                |
| **Customer support**      | Respond quickly to customer complaints                     |
| **Fraud screening**       | Use WEpayments anti-fraud system                           |
| **Refund proactively**    | Offer refunds before customer initiates chargeback         |

### What to do when a chargeback occurs

| **Step**                    | **Action**                                                          |
| :-------------------------- | :------------------------------------------------------------------ |
| **1. Receive notification** | WEpayments notifies you of the chargeback                           |
| **2. Gather evidence**      | Collect transaction details, delivery proof, customer communication |
| **3. Submit defense**       | Provide evidence to our team for chargeback defense                 |
| **4. Await decision**       | Card issuer makes final decision (can take 30-90 days)              |

> 💡 Chargeback fees may apply. Contact support for details.

## MED notifications (PIX fraud returns)

The **Special Return Mechanism (MED)** is a Central Bank of Brazil process that allows banks to return funds from suspected fraudulent PIX transactions.

### How MED impacts approval

| **Aspect**     | **Description**                                                 |
| :------------- | :-------------------------------------------------------------- |
| **Trigger**    | Customer fraud complaint or bank suspicion                      |
| **Impact**     | Funds frozen during investigation                               |
| **Outcome**    | Funds returned (if fraud confirmed) or released (if legitimate) |
| **Prevention** | Maintain transaction records and delivery proofs                |

## Best practices to improve approval rates

| **Practice**                             | **Why it helps**                        |
| :--------------------------------------- | :-------------------------------------- |
| **Validate email addresses**             | Email is a key fraud signal             |
| **Use free lists for trusted customers** | Reduces false positives                 |
| **Monitor chargeback ratios**            | High ratios may lead to restrictions    |
| **Provide clear billing descriptors**    | Reduces customer confusion and disputes |
| **Respond quickly to compliance**        | Prevents transaction holds              |