You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me with booking a flight ticket from IAD to PHL?

ASSISTANT: Can you please share your travelling dates?

USER: My travelling dates are from June 19-21.

ASSISTANT: Do you have class preference?

USER: I am comfortable with any class.

ASSISTANT: May I know your name?

USER: Brian Walker here.

ASSISTANT: We found American Airline with fare 100 and flight number is 1019 with direct flight. Shall I proceed with the booking?

USER: You can proceed with booking.

ASSISTANT: Your booking is done.

USER: Thank you for the help.

ASSISTANT: Thank you for choosing us.