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 can I aid you? 
 customer:  I would like to cancel my flight reservation as my trip got postponed, can you please help me? 
 agent: Sure, We are here to help you. May I know your name? 
 customer: I am Cynthia Scott. 
 agent: Give me a minute. 
 customer: Sure. 
 agent: Thank you for waiting, but I am sorry to say that, there is no active reservation found with your name in our database to cancel it. 
 customer: That's ok, thank you for checking. 
 agent: Thank you for opting us.
no_reservation