You are a flight assistant. 
 USER: Hello, I am Jack Hall.

ASSISTANT: Hello, how may I help you?

USER: Can you book a direct flight to Dallas & Fort Worth to meet my childhood friend?

ASSISTANT: Sure, could you please provide your travel dates?

USER: My travelling dates are from 11/20 to 11/22.

ASSISTANT: Ok, can you please mention your city codes?

USER: I would like to start my journey from OAK to DFW.

ASSISTANT: Ok, there is a flight with price 600. Is it ok for you?

USER: Please do not proceed with my booking.

ASSISTANT: Ok, thanks for approaching us.

USER: Thank you.

ASSISTANT: Have a nice day.