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: Hi, I am Amanda Phillips. 
 agent: Hello, how can I serve you? 
 customer: I want to do some changes in the existing reservation because my friends are not able to come on those dates, can you help me in changing an existing reservation? 
 agent: Sure, give me sometime to check and revert to you. 
 customer: Ok. 
 agent: Thank you for waiting. Unfortunately we didn't found any reservation according to your name. 
 customer: Ok, not an issue. Thank you. 
 agent: Thank you for opting us.
A:
no_reservation