You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I am Brandon Robinson. Can you help me in booking my flight ticket from IAD to SFO?

ASSISTANT: Sure, may I know your planned trip dates?

USER: My trip dates will be Dec 23rd to Dec 25th.

ASSISTANT: Which class do you prefer either economy or business?

USER: I am comfortable with any class.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: May I know your arrival and depart timings?

USER: My depart time should be in the afternoon.

ASSISTANT: Please be on hold.

USER: Sure.

ASSISTANT: Sorry,there are no flights found on your specified routes.

USER: Not an issue, thank you.

ASSISTANT: Thank you for availing us.