You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,how can I help you?

USER: I want to book a flight ticket.

ASSISTANT: OK,Let me know your good name please?

USER: OK, I am Andrew Lewis.

ASSISTANT: Andrew Lewis ,May the source and destination of your journey?

USER: Yes, my source is CA - SFO and destination is NC - CLT.

ASSISTANT: Can you inform the dates of your journey?

USER: My travelling dates are starting Nov 10 and returning Nov 12.

ASSISTANT: Sorry,based on given information we do not have any flight ticket.

USER: OK, thanks for your service.

ASSISTANT: Have a nice day.