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 assist you? 
 customer: I want to cancel my reservation due to some health issues, so please help me. 
 agent: Sure, I am here to help you. 
 customer: Please check the reservation on the name of Emma Green. 
 agent: Please wait for a moment. 
 customer: Sure. 
 agent: Emma Green, no reservation has been found on your name in our database. 
 customer: No problem, thank you. 
 agent: Thank you for reaching us.
no_reservation