Braintree 支付 - 沙盒交易的处理器拒绝（2409）错误

根据 Braintree 支付 - 沙盒交易的处理器拒绝（2409）错误进行故障排除

javascript
var gateway = braintree.connect({
  environment: braintree.Environment.Sandbox,
  merchantId: 'your_merchant_id',
  publicKey: 'your_public_key',
  privateKey: 'your_private_key'
});
var transaction = {
  amount: '10.00',
  paymentMethodNonce: 'your_payment_method_nonce'
};
gateway.transaction.sale(transaction, function (err, result) {
  if (err) {
    console.error(err);
    return;
  }
  if (result.success) {
    console.log('Payment successful!');
  } else {
    console.error(result.message);
  }
});