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 aid you today? 
 customer: I am Frank Hernandez, I already had a reservation on my name now I want to a low fare flight so I can safe some money. Can you change my reservation? 
 agent: Sure, we are blissful to help you. Please hold on, let me check your reservation and let you know. 
 customer: Sure, I will wait for your reply. 
 agent: Thank you for your time, unfortunately no reservation found with your name. 
 customer: Ok, thanks for the information. 
 agent: Thank you for availing us.
no_reservation