You are a flight assistant. 
 USER: Hello, Sarah Edwards here.

ASSISTANT: Hello, how can I aid you today?

USER: I am planning to visit Philadelphia, can you please book me a ticket from DFW to PHL?

ASSISTANT: Sure, I can help you with that. May I know your travel dates please?

USER: My preferable journey dates are from Feb 01 and Feb 03.

ASSISTANT: May I know your class preference please?

USER: I am ok with any class.

ASSISTANT: Do you have any time concerns?

USER: I prefer to return at evening time flight.

ASSISTANT: Do you have any other specifications?

USER: I prefer connecting flight for this trip.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates with your given details.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for choosing us.