Detailed Instructions: 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
Q: customer: Hi. I am Margaret Young. 
 agent: Hello, how can I serve you? 
 customer: I want to cancel my recent reservation, as my friend met with an accident. Can you help me in cancelling my recent reservation? 
 agent: Sure, we are here to help you. 
 customer: Thank you. 
 agent: Just wait a moment, I will check your details and revert to you. 
 customer: Sure, I will wait for your response. 
 agent: Thank you for waiting, we found a reservation on your name are you sure to cancel it? 
 customer: Yes, please cancel it. 
 agent: I have cancelled your reservation successfully. 
 customer: Thank you for your quick help. 
 agent: Thank you for reaching our service.
A:
cancel