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: Hello. 
 agent: Hello, how may I help you? 
 customer: I would like to change my reservation due to some health issues, can you please help me out with that? 
 agent: Sure, I am here to help you. May I know your name? 
 customer: Myself Lisa Nelson. 
 agent: Thank you. Please wait for a while, let me check your reservation status. 
 customer: Sure. 
 agent: Sorry, I have not found any reservation under your name in our database. 
 customer: Ok, no problem. Thank you for checking out. 
 agent: You are most welcome.
A:
no_reservation