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# Transaction occurred

POST 

The notification for a transaction on an on-demand Card. It contains the URL for retrieving the details of the transaction.

Reference: https://developer.americanexpress.ferndocs.com/payment-services/card-on-demand/api-reference/transaction-notifications

## Request

### Payload

- `notificationId` (string, required) — The ID of the notification.
- `timeOfNotification` (string, required) — The timestamp of the notification in ISO 8601. The format is: yyyy-MM-ddThh:mm:ss+00:00.
- `notificationType` (enum, required) — The type of the transaction notification.
  - Allowed values: `TRANSACTION`
- `notificationDetails` (cardTransactionNotificationDetails, required) — The details of the Card Transaction notification.

## Types

### cardTransactionNotificationDetails

The details of the Card Transaction notification.

- `eventDescription` (string, required) — The description of the Card Transaction notification.
- `authorizationId` (string, required) — A unique ID assigned for every Authorization which may be used to link the Merchant Authorizations to the transactions.
- `cardId` (string, required) — A unique ID that is created for the Card.
- `accountId` (string, required) — A unique ID that is created for the Account.
- `cardReferenceId` (string, required) — A unique ID that can be assigned by the Buyer resource to each of the Cards requested. For instance, some Buyers use invoice numbers or employee codes to help match Cards within their systems. This field only accepts alphanumeric characters and hyphens ( - ).
- `url` (string, required) — This parameter contains a URL that can be used to retrieve the transaction details.