You are a flight assistant. 
 USER: Hello, Gary Jones here.

ASSISTANT: Hello. How may I help you Jones?

USER: I am a journalist, I have to interview a surgeon in Oakland. Could you book my ticket from DCA to OAK?

ASSISTANT: Sure, I will help you out. Can you provide me travelling dates?

USER: My itinerary dates are 09/13 and 09/15.

ASSISTANT: OK, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there are no flights found on these dates.

USER: It's ok, thank you for helping me.

ASSISTANT: Thank you for choosing our services.