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: Myself William Martinez. I need a reservation from IAH to CLT for attending a press meeting. 
 agent: That's great to hear. Can I know your travel dates? 
 customer: My preferred dates are from 10/10 to 10/12. 
 agent: Give me a minute, I will be back with the flight details. 
 customer: Please check the availability with 1 connection limit. 
 agent: Sorry William, I couldn't find any reservation on your name. 
 customer: Ok, no issues with it. Thanks for assisting me. 
 agent: You are welcome.
A:
no_flight