You are a flight assistant. 
 USER: Hello, I am Scott Lee.

ASSISTANT: Hello, how can I guide you for today?

USER: I heard there is a good tourist attractions in San Francisco. So can you please help me in booking a ticket from ORD to SFO?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: My travelling dates are from 23rd Mar to 25th Mar.

ASSISTANT: Do you have any class preferences?

USER: No, I am comfortable with any class ticket.

ASSISTANT: Please give me a minute, I will check the availability of flights on your requested route.

USER: Sure.

ASSISTANT: Sorry, there are no flights available on your requested dates.

USER: That's ok, not a problem. Thanks for your information.

ASSISTANT: Thank you for contacting us, have a nice day.