Q: 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. 
 customer: My name is William Collins. 
 agent: How can I aid you? 
 customer: I have already booked my ticket to Boston but due to an medical emergency, my trip got cancelled. 
 agent:  Ok, Do you want to cancel the trip now ? 
 customer: Yes, can you help me with that? 
 agent: Sure, I can do this favor to you. Please wait a while. 
 customer: Ok, take your time. 
 agent: Thanks for your time. We didn't found any reservation by this name. 
 customer: That's fine. Thank you for your time. 
 agent: Thank you for picking us.
A:
no_reservation