# Handle Errors

This guide covers how to [handle gasless transfer errors](#handle-gasless-transfer-errors) and [handle native TON transaction errors](#handle-native-ton-transaction-errors), plus [best practices](#best-practices) for fee management and memory cleanup.

## Handle Gasless Transfer Errors

Gasless transfers can fail for reasons specific to the paymaster model. Wrap calls to [`account.transfer()`](https://docs.wdk.tether.io/sdk/wallet-modules/api-reference#transfer-options-config) in `try/catch` blocks:

{% code title="Gasless Transfer Error Handling" lineNumbers="true" %}

```javascript
try {
  const result = await account.transfer({
    token: 'EQ...',
    recipient: 'EQ...',
    amount: 1000000000
  })
  console.log('Transfer hash:', result.hash)
} catch (error) {
  if (error.message.includes('insufficient jetton balance')) {
    console.error('Please add more Jetton tokens to your wallet')
  } else if (error.message.includes('insufficient paymaster balance')) {
    console.error('Please add more paymaster tokens for gas fees')
  } else if (error.message.includes('invalid address')) {
    console.error('The recipient address is invalid')
  } else if (error.message.includes('max fee')) {
    console.error('The transfer fee exceeds your configured maximum')
  } else {
    console.error('Transfer failed:', error.message)
  }
}
```

{% endcode %}

## Handle Native TON Transaction Errors

Native TON transactions sent via [`account.sendTransaction()`](https://docs.wdk.tether.io/sdk/wallet-modules/api-reference#sendtransaction-tx) can fail for standard reasons:

{% code title="Transaction Error Handling" lineNumbers="true" %}

```javascript
try {
  const result = await account.sendTransaction({
    to: 'EQ...',
    value: 1000000000
  })
  console.log('Transaction hash:', result.hash)
} catch (error) {
  if (error.message.includes('insufficient balance')) {
    console.error('Not enough TON to complete transaction')
  } else {
    console.error('Transaction failed:', error.message)
  }
}
```

{% endcode %}

## Best Practices

### Manage Fee Limits

Set `transferMaxFee` when creating the wallet to prevent gasless transfers from exceeding a maximum cost. You can retrieve current network rates using [`wallet.getFeeRates()`](https://docs.wdk.tether.io/sdk/wallet-modules/api-reference#getfeerates):

{% code title="Fee Management" lineNumbers="true" %}

```javascript
const feeRates = await wallet.getFeeRates()
console.log('Normal fee rate:', feeRates.normal, 'nanotons')
console.log('Fast fee rate:', feeRates.fast, 'nanotons')
```

{% endcode %}

### Dispose of Sensitive Data

Call [`dispose()`](https://docs.wdk.tether.io/sdk/wallet-modules/api-reference#dispose) on accounts and wallet managers to clear private keys and sensitive data from memory when they are no longer needed:

{% code title="Memory Cleanup" lineNumbers="true" %}

```javascript
account.dispose()

wallet.dispose()
```

{% endcode %}

{% hint style="warning" %}
Always call [`dispose()`](https://docs.wdk.tether.io/sdk/wallet-modules/api-reference#dispose) in a `finally` block or cleanup handler to ensure sensitive data is cleared even if an error occurs.
{% endhint %}