You will be given a definition of a task first, then some input of the task.
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 best oblige you today? 
 customer: Due to relocation of my fashion show computation, I need to change my existing reservation. Can you aid me to change my recent reservation? 
 agent: Sure, we are ecstatic to help you. 
 customer: Thank you. 
 agent: Can I have your name to trace your details? 
 customer: Sure, you can trace my status on the name of Katherine Baker. 
 agent: Please wait for a moment, I will check the reservation list and notify you. 
 customer: Sure. 
 agent: Thank you for waiting, we are sorry to say that no reservation was found based on your name. 
 customer: That's Ok, thanks for your information. 
 agent: Thank you for choosing us.
Output:
no_reservation