Update card account reservation

Here, you will learn how to update account reservations in Tuum when card-related accounts are located within Card API.

If you are working with Tuum setup where card-related accounts are located within Tuum core, you should use the appropriate Account API endpoints instead.

Use case

In this example, we will demonstrate how to update an account reservation for a card account. This operation may be required when the amount of the original reservation needs to be modified. The following example extends the previous Create card account reservation example.

Use case data	API parameters with values
The unique reservation ID that is obtained from the Create card account reservation.	...reservations/C001664282461/change
New reservation amount. Note: The final reservation amount may differ from the amount requested if fees apply to the given transaction type. Fees are applied only if the transactionTypeCode is provided and the directionCode is OUT.	"money": { "amount": 55, "currencyCode": "EUR" },
The reservation is created by transaction R0000150 in the external system named ONLINE.	"source": { "sourceName": "ONLINE", "sourceRef": "RES_2" }
Reservation details	"details": "123 Main Street, Bratislava, SVK",
Merchant information	"merchantInfo":"Kaufland Bratislava, SVK",
Additional information related to the transaction.	"additionalInfo": "Additional info"
Transaction type code Note: Must be provided if fees are calculated in CMS.	"transactionTypeCode": "CARD_PUR"
Account balance must be checked before making the reservation.	"checkBalance": true
The ID of the card to which the funds are to be added. Note: It is recommended to always provide the card ID. This is necessary to identify the correct card-level price list in cases where multiple cards are associated with the same account.	"cardId": "C001664282657"

Sample API call

To update an account reservation for a card account, use the following endpoint:

https://card-api.sandbox.tuumplatform.com/api/v1/reservations/{reservationId}/change

Learn more about the update card account reservation endpoint in the Tuum developer portal.

Sample request

The sample request body is as follows:

JSON

{
  "money": {
    "amount": 55,
    "currencyCode": "EUR"
  },
  "cardId": "C001664282657",
  "source": {
   "sourceName": "ONLINE",
    "sourceRef": "RES_2"
  },
  "details": "123 Main Street, Bratislava, SVK",
  "merchantInfo": "Kaufland Bratislava, SVK",
  "additionalInfo": "Additional info",
  "transactionTypeCode": "CARD_PUR",
  "checkBalance": true
}

cURL

Sample response

Below you will find the response to the API request:

Response

{
    "errors": null,
    "validationErrors": null,
    "data": {
        "reservationId": "C001664282461",
        "accountId": "C001664282649",
        "amount": 55.28,
        "currencyCode": "EUR",
        "directionCode": "OUT",
        "source": {
            "sourceName": "ONLINE",
            "sourceRef": "RES_2"
        },
        "details": "123 Main Street, Bratislava, SVK",
        "merchantInfo": "Kaufland Bratislava, SVK",
        "additionalInfo": "Additional info",
        "reservationDTime": "2025-11-03T15:00:00.438234Z"
    }
}

Result

The outcome of the API call is updated card account reservation amount, increasing from 55.00 to 55.28, which includes a 0.28 fee.