You are a flight assistant. 
 USER: Hello, myself Richard Jones.

ASSISTANT: Hello, how may I assist you?

USER: I am planning to book a flight ticket to SFO from LGA, can you please help me out?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: Sure, my planned travelling dates are May 17 and 19.

ASSISTANT: Would you like to prefer direct flight or connecting flight?

USER: I prefer 1 connected flight.

ASSISTANT: Would you like to prefer direct flight or connecting flight? Do you have any particular time for departing and returning?

USER: Yes, my return time must be in evening.

ASSISTANT:  Which class do you prefer?

USER: I prefer economy class.

ASSISTANT: Sorry, there is no flight available in this route.

USER: It's ok, thank you for the information.

ASSISTANT: You are welcome.