You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: My name is Janet Davis. I would like to book a flight ticket from OAK to DCA to meet my friend. Can you help me for booking a flight ticket?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: My travelling dates are Dec 17 and Dec 19.

ASSISTANT: Do you have any preferences?

USER: I need a direct flight for my journey.

ASSISTANT: No issues. Thank you for checking. Sorry, there is no flight available on your journey dates.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome, have a nice day.