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: Hi, I am Daniel Nelson. 
 agent: Hello Nelson. What can I do for you? 
 customer: I need to cancel my recent reservation as I met with an accident and my leg got fracture and I am unable to travel. Can you please help me out with this? 
 agent: Sure Daniel Nelson, Wait for a while. 
 customer: Ok, take your time. 
 agent: Sorry , no reservation done on the name of Daniel Nelson in previous days. 
 customer: Thanks for your information. 
 agent: Thank you for approaching us, have a nice day.
no_reservation