Preventing Duplicate Transactions

In order to avoid the possibility of duplicate transactions caused by such reasons such as having a buyer click twice before an order can be confirmed if no prevention or having the network being disconnected, causing a retry, we added a safeguard mechanism to our checkout calls whereby a UUID generated before the call to the checkout API and independent of client retries will be blocked by the ACME servers.

A duplicate check will return a 409 http response code.

Please use the following header x-acme-request-uuid and create a UUID in the following form: 


In its canonical textual representation, the sixteen octets of a UUID are represented as 32 lowercase hexadecimal (base 16) digits,
displayed in five groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters (32 alphanumeric characters and
four hyphens). For example: 123e4567-e89b-12d3-a456-426655440000

HTTP Request Header


B2C Checkout Placing an order with a shopping cart
Event Templates - B2C
APIs to help you market your events. Ex: A calendar of days where the event is available and not sold out
Shopping CartBuilding and storing shopping carts on our site
ReservationsReservations API to reserve tickets while you are performing a checkout