Q: 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: Hello. 
 agent: Hello, what can I assist you for today? 
 customer: I want to change my trip dates because I had an important meeting, so that I am unavailable to catch the flight. Can you alter my ticket? 
 agent: Ok, please provide your name to check the existing reservation. 
 customer: Sure, the previous reservation is done under the name John Mitchell. 
 agent: Sorry, there is no reservation on your name to change. Do you have any other requirements? 
 customer: Ok, no problem, I will search  any other way. 
 agent: Ok, thank you for using our service. Have a great day ahead. 
 customer: Thank you for your information. 
 agent: Most welcome.
A:
no_reservation