READ_ORDERSrejectReason and venueCode when the status is REJECTED.status is PENDING_SUBMIT or SUBMITTED, until it reaches a final state.status is UNKNOWN. Your funds are still reserved and a background process is resolving the truth. Never re-place the order.400 VALIDATION_ERROR for a malformed id, 404 NOT_FOUND with the message "Order not found".An order belonging to another user returns 404, never403. The API never confirms that someone else's id exists.