You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you at this moment?

USER: I want to book a flight ticket from PHL to San Francisco SFO. Can you find a flight ticket for me?

ASSISTANT: Sure, do you need a lay by in between the journey?

USER: Ok, I need a direct flight.

ASSISTANT: On which dates would you like to travel?

USER: Ok, my planned trip dates are on Jan 21 and return on Jan 23.

ASSISTANT: Do you have any other preferences?

USER: No, thanks for asking.

ASSISTANT: There are no flights found on your requested dates.

USER: Ok, not an problem.

ASSISTANT: May I know your good name please?

USER: Yes, I am Eric Harris.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your help.