You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help today?

USER: I am Joshua Thomas. I have to book a flight ticket  that I am unable to do, could you please help me in booking flight ticket on dates 10/19 and 10/21?

ASSISTANT: Sure, kindly share your airport codes.

USER: My airport codes are PHL and ATL.

ASSISTANT: Do you have any connection preference?

USER: I need a direct flight.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: Ok, no problem. That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us.