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. This is Stephen Jones. 
 agent: Hello. How can I assist you? 
 customer: I am planning to travel to PHX to meet my friend,can you please help me to book a flight ticket from SFO? 
 agent: Can you please mention your travelling dates? 
 customer: I want to depart on May 14th and return on May 16th. 
 agent: Let me know your depart and arrival timings? 
 customer: I would like to Return in the morning. 
 agent: Do you want connecting flight? 
 customer: Yes, I want a single connecting flight. 
 agent: Ok, please wait. 
 customer: Sure. 
 agent: Sorry, no flights found on your route. 
 customer: It's ok,  thank you for your information. 
 agent: Thank you for connecting with us.
A:
no_flight