You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I need to attend a seminar at San Francisco, can you help me to book a flight ticket from CLT to SFO?

ASSISTANT: Sure, I am happy to help you. Can I have your travelling dates?

USER: My travel dates are July 21 and July 23.

ASSISTANT: Do you prefer any break in between journey?

USER: I prefer direct flight for this trip.

ASSISTANT: Is there any other specifications for you?

USER: No.

ASSISTANT: May I know your good name?

USER: I am Larry Brown.

ASSISTANT: Sorry, no flights are available on your journey routes.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for contacting us.