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
Input: customer: Hello. 
 agent: Hello, how may I render you today? 
 customer: I want to change airport codes in my existing reservation, can you please help me? 
 agent: Sure, we are here to help you. May I know your good name? 
 customer: Thank you for your positive response. The ticket is reserved under the name Emily Thomas. 
 agent: Ok, please wait for a minute. 
 customer: Sure, I will wait for your response. 
 agent: Thanks for waiting, there is no active reservation found on your name. 
 customer: No issue, anyway thank you for checking. 
 agent: Thank you for reaching us.
Output:
no_reservation