You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you today?

USER: I am William Harris. Please book me a ticket from ATL to PHL to meet my family.

ASSISTANT: Sure, when did you planned to travel?

USER: I would like to fly on 10/02 and return on 10/04.

ASSISTANT: Do you have any other specifications to be met?

USER: I prefer direct flight.

ASSISTANT: Sorry to say, We do not found any flights running in your planned dates.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you.