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: Hi. 
 agent: Hello. 
 customer: I am Nicole Lee. 
 agent: How can I help you Lee? 
 customer: Can you help me to book a flight with 500 price limit? 
 agent: Ok, please tell us your travelling dates. 
 customer: My trip dates are 01/18 and 01/20. 
 agent: May I know your travel airport codes? 
 customer: My airport codes are SFO and AUS. 
 agent: I found a direct flight for you, shall I book? 
 customer: Sorry, I need a connecting flight. 
 agent: I am sorry no flight with 1 connection is available on your route. 
 customer: Ok, no issues. Thank you for your time. 
 agent: You are most welcome.
Solution:
no_flight