You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. Is there any help that you are seeking from my side?

USER: I am Katherine Evans want to visit Austin to meet my friends, can you book a ticket on 01/21 and 01/23?

ASSISTANT: Yes, I am gleeful to help you. Will you please share your exact regional airport codes of your trips?

USER: Sure, I want to fly from IAD to AUS.

ASSISTANT: Give me a moment, so that I can check the flight and get back to you with flight details.

USER: Ok.

ASSISTANT: Thank you for your patience, I could not any flight on your requested routes to reserve a flight ticket for you.

USER: That's ok, thank you for the information.

ASSISTANT: It's my pleasure, have a nice day.