You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am Elizabeth Moore. I want to book a ticket from OAK to IAD. Can you please help me out?

ASSISTANT: Sure, can you please share your preferable travel dates?

USER: My travelling dates are 03/13 and 03/15.

ASSISTANT: Ok, let me check for the availability of flight on this route.

USER: Sure, take your own time.

ASSISTANT: Elizabeth, I am sorry to inform you that there is no flight available at your request.

USER: That's fine. Thank you for your help.

ASSISTANT: Thank you for contacting us.