You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: Sandra Phillips here. Can you help me in booking the flight ticket from SFO to PHL?

ASSISTANT: Sure, may I know your travelling dates, please?

USER: My trip dates are 02/10 and 02/12.

ASSISTANT:  Is there any particular timings in your departure and arrival?

USER: I want to return in afternoon.

ASSISTANT: Do you need any specifications for this reservation?

USER: I want a single connecting flight. I prefer to travel in economy class.

ASSISTANT: Sorry, there are no flight tickets available on your journey dates.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching our service.