Detailed Instructions: 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
Problem:customer: Hello. 
 agent: Hello. How can I aid you? 
 customer: I am looking to book a flight ticket from DEN to LAX. Can you help me for that? 
 agent: Sure, We are here to help you. Can I know your travelling dates? 
 customer: My travelling dates are Dec 13 and Dec 15. 
 agent: Do you need any break? 
 customer: I prefer to book a direct flight in my journey. 
 agent: May I know your name? 
 customer: My name is Samantha Hall. 
 agent:   We are unable to provide flight in between your journey routes due to some technical up-gradation at destination airport. 
 customer: That's ok, thank you for checking. 
 agent: Thank you for reaching us.
Solution:
no_flight