You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I want to book a flight from PHL to attend a meeting at SFO. Can you find a flight for me?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: I will travel on June 29 and return on July 1st.

ASSISTANT: Can I know your name please?

USER: My name is David Jackson.

ASSISTANT: Do you need any specifications in airlines?

USER: I prefer a direct flight.

ASSISTANT: Can I know is there any other preferences?

USER: No.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us.