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
Problem:customer: Hi. 
 agent: Hello. How may I help you? 
 customer: I want to change my reservation, can you help me? 
 agent: May I know your name please? 
 customer: I am Kenneth Martinez. 
 agent:  Kenneth Martinez sorry, no reservation found as per your preferences. 
 customer: No problem, thanks for checking. 
 agent: Thank you for choosing us.
Solution:
no_reservation