---
title: References & Troubleshooting
slug: references-and-troubleshooting
docTags: 
createdAt: 2026-10-09T09:20:43.857Z
---

## Required fields

A transaction is checked against these fields before it's sent off to Amex. If one is missing, it's declined without reaching Amex.

| Field                                                                            | Where you set it                              | Set by            |
| -------------------------------------------------------------------------------- | --------------------------------------------- | ----------------- |
| `dba_name`                                                                       | Configuration                                 | You               |
| `merchant_category_code`                                                         | Configuration                                 | You               |
| `merchant_email`                                                                 | Configuration                                 | You               |
| `phone_number`                                                                   | Configuration                                 | You (recommended) |
| `line_1`, `city`, `postal_code`, `country_code`                                  | Merchant address                              | You               |
| `amex_region_code`                                                               | Merchant address                              | You               |
| Routing rule with `american_express`                                             | Configuration (`transaction_routing_rule_id`) | You               |
| `amex_config`: SE number, Seller ID, payfac name, origin, region, submitter code | Account default configuration                 | Toro              |
| Online PIN keys                                                                  | Account default configuration                 | Toro              |

## Troubleshooting



| What you see                                                                        | Likely cause                                          | What to do                                                                                                                                                                                      |
| ----------------------------------------------------------------------------------- | ----------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| The reader rejects the Amex card straight away, for example asking for another card | The reader doesn't have the latest card configuration | See [Before you test](docId\:yyk-Osvz2pCb-Dow0sS2E).                                                                                                                                            |
| The receipt shows a different `acquirer`                                            | The POI isn't using your rule                         | Check `transaction_routing_rule` in `GET /pois/{id}/context`. Check the rule's `current_version_id` is your latest version, and that no configuration lower in the chain sets a different rule. |
| The transaction fails with "unable to select an acquirer"                           | Every acquirer's weight was `0` for that transaction  | Check the rule's conditions match the expected card brand.                                                                                                                                      |
| The transaction fails after you change the rule                                     | The rule refers to a parameter it doesn't define      | Make sure every value in `actions.onSuccess.context` is defined in `localParams`. See [Add a version](docId\:zl1hcmoHGYj1rqE01TK-k).                                                            |
| The transaction fails with a message about `merchant_email`                         | No email set                                          | Set `merchant_email` on the configuration.                                                                                                                                                      |
| The transaction fails with a message about the address or region code               | Merchant address incomplete                           | Set `line_1`, `city` and `amex_region_code` on the merchant's address.                                                                                                                          |
| Amex declines the transaction                                                       | Amex's decision on the card or the transaction        | Check `response_code` and `response_reason` on the receipt. If you think the decline is wrong, contact Toro support with the receipt `id`.                                                      |

When you contact Toro support, include the terminal's `poi_id`, the receipt `id` and the time of the transaction.