Confirming REJECTED transactions leads to HTTP 5xx
Handle customer product deactivations gracefully
Validate country codes
Validate callback URLs
Subservices for products under the Gift Cards service
Allow UUID and ULID formats for purchaser_id
Response validation failures due to bad payment product data
Launch product subservices, Support additional_identifier fields
Error code 1009503 (HTTP 503) to denote system maintenance
Better support for OpenAPI SDK generators by defining operationId