Given the task definition and input, reply with output. In this task, you are given a conversation between a flight agent and the customer. You are given 4 options and you need to select the goal of the conversation. It is provided as part of customer's context, which has to be one of the following: `book`: Make a new reservation, `cancel`: Cancel an existing reservation, `no_flight`: No flight found for the customer's preference, `no_reservation`: No reservation / No change / No cancellation was made in the conversation, mostly enquiring details

customer: Hello. 
 agent: Hello. How may I aid you today? 
 customer: I am looking to cancel the flight ticket which is booked in the last week because I am unable to travel due to some health issues. Can you please help me to cancel the ticket? 
 agent: Sure, please wait a moment, let me check. 
 customer: Thank you for considering my request. Take your time. 
 agent: Before proceeding, can you please mention your name? 
 customer: My name is Anna Lee. 
 agent: Hold a moment. 
 customer: Ok. 
 agent: Sorry Lee, there are no active reservation to cancel on your name. 
 customer: It's ok, not a problem with that. Thank you for your valuable time. 
 agent: Thank you for reaching our service.
no_reservation