You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: My name is Gregory Hill. I am looking to book a flight ticket to meet my friend in Austin, can you help me for booking a flight ticket from IAD to AUS?

ASSISTANT: Sure, can you share your trip dates?

USER: My travelling dates are Dec 27 and Dec 29.

ASSISTANT: Give me a minute.

USER: Sure, I will wait for your response.

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

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

ASSISTANT: Than you for reaching us.

USER: Welcome, have a nice day.