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 support you today? 
 customer: I am Lisa Hill. Please book me a ticket from ATL to LGA at evening time. 
 agent: Sure, I am glad to help you. May I know your journey dates please? 
 customer: Thank you. I have planned to travel on 05/19 and 05/21. 
 agent: Do you need any halt in between your journey? 
 customer: I need a direct flight. 
 agent: Is there any class preferences? 
 customer: I am ok with any flight. 
 agent: Thanks for your details, please wait. 
 customer: Ok, I will wait. 
 agent: Thank you for waiting, no flights were found based on your schedule. 
 customer: Ok, no problem. Thank you. 
 agent: Thank you for choosing us.
A:
no_flight