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. 
 agent: Hello, how may I help you today? 
 customer: I want to travel from ATL to LAX, can you please book me a flight ticket? 
 agent: Sure, help me with the trip dates? 
 customer: My travel dates are from Dec 8th to Dec 10th. 
 agent: Do you have any preferences? 
 customer: I want a break in between my journey. 
 agent: May I know your name please? 
 customer: I am Karen Davis. 
 agent: Thank you for your details, we do not found any flights running in your desired routes. 
 customer: Ok, no problem. Thank you. 
 agent: Thank you for reaching us. Have a nice day.
no_flight