Given the task definition and input, reply with output. 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: Hi, I am Amy Hall. 
 agent: Hello, how can I serve you today? 
 customer: I need your help in ticket reservation from LGA to PHL. 
 agent: Sure, may I know your journey dates? 
 customer: My journey dates are from 03/16 to 03/18. 
 agent: Ok, please wait a moment. 
 customer: Sure. 
 agent: There is a flight found with direct connection of fare 100. 
 customer: I need one connection in my journey. 
 agent: Sorry there is no flight found on single connection. 
 customer: Ok, no issue. 
 agent: Thanks for connecting us, have a great day. 
 customer: Thank you.
no_flight