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. 
 agent: Hello, how can I assist you now? 
 customer: I need your assistance about modification of my reservation which I have done long back to travel in the next month to Chicago but all of sudden my schedule got postponed to some other as on of my relative got expired last night. Can you please help me about that? 
 agent: Sure, I am happy to help you with that. 
 customer: Thank you for your positive response. 
 agent: Can I have your name please? 
 customer: Sure, my name is Timothy Thompson. 
 agent: Ok, please wait a moment. 
 customer: Sure, I will wait. 
 agent: Sorry Robert Perez, no reservation has found under your name to change. 
 customer: Not a big deal, anyways thank you for the information. 
 agent: Thank you for choosing us, have a good day.
no_reservation