You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Jack Garcia. I am planning to book a ticket from IAH to OAK. Can you please help me out?

ASSISTANT: Sure, may I know your trip dates?

USER: My travelling dates are 11/28 and return back on 11/30.

ASSISTANT: Sorry, there is no flight on your requested dates.

USER: That's fine. Thank you.

ASSISTANT: Thank you for reaching us.