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
Q: customer: Hello. 
 agent: Hello. How can I aid you today? 
 customer: My name is George Hill, I want to book a flight ticket from HOU to SEA, can you help me? 
 agent: Sure, I am here to help you. May I know your travel dates please? 
 customer: My trip dates are Aug 09 and Aug 11. 
 agent: Ok, do you have any other specifications? 
 customer: My return time is afternoon. 
 agent: Ok, hold on for a moment. Let me check the best available flight for you. 
 customer: Sure, I need a connecting flight. 
 agent: Sorry George Hill, there are no flights available on your requested dates. 
 customer: Ok, no problem. Thank you. 
 agent: Welcome, thank you for choosing us. Have a great day.
A:
no_flight