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. How can I assist you? 
 customer: I am Ashley Allen. I am planning to change an existing  reservation, due to health issue. Can you please change my reservation? 
 agent: Sure, please give me a minute. 
 customer: Sure. 
 agent: Sorry Allen, there is no reservation available on your name. 
 customer: That' s fine, thank you for your quick response. 
 agent: You are welcome.
A:
no_reservation