You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: Steven Hill here. I'm planning to visit Austin, can you please book a ticket from SEA to AUS?

ASSISTANT: Sure, can I know your preferable dates?

USER: Sure, my planned departure and return travel dates are 31st of December and 2nd of January.

ASSISTANT: I am sorry, there are no flights available.

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

ASSISTANT: Thank you.