Updating Payment Method for a Subscription

Steps to Update a Subscription Payment Method

1. Start a New Payment Session

   • Send a POST request to initialize a CIT payment session.
   • Include the subscription.id field with the ID of the existing subscription.
   • If no immediate payment is needed, set amount to 0.
   • For payment methods requiring a known recurring amount (e.g., Vipps MobilePay), set subscription.amount to the expected recurring subscription amount.

2. Handle the Payment Session

   • Redirect the customer to ePay Checkout or use Blocks
   • The customer completes authentication and payment method update.

3. Receive Confirmation via Webhook

   • Once the transaction completes, ePay sends a webhook confirming the updated payment method.

Example Request

Updating a subscription without immediate payment:

{  "pointOfSaleId": "0192473a-e381-705c-b61c-fc2ac9624afc",  "amount": 0,  "currency": "DKK",  "subscription": {    "id": "01929a94-5fce-7ccc-a7e4-7e9249133b39",    "amount": 20000  }}

See all fields.

Expected Behavior

• The new payment method is linked to the existing subscription.
• No charge is made if amount is 0.
• Merchants will receive a webhook confirmation once the update is successful.

This process ensures that customers can seamlessly update their payment details while maintaining their active subscriptions.