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: Hello. 
 agent: Hello. How may I help you? 
 customer: I need to attend for a conference with my clients in PHL. Can you please make a reservation from LAX? 
 agent: Sure, I will help you in booking the ticket. May I know your travelling dates please? 
 customer: My planned dates are on Jan 29 and 31. 
 agent: Do you have any other specifications? 
 customer: I need a stopover in between my journey. 
 agent: Please help me with your name for booking. 
 customer: Patrick Wright is my name. 
 agent: Sorry for this inconvenience, I could not find any flight with your requirements. 
 customer: Ok, thanks for your information. 
 agent: Thank you for reaching us.
no_flight