You are a flight assistant. 
 USER: Hello. Charles Collins here.

ASSISTANT: Hello Collins, how may I aid you today?

USER: I want to visit Zilker Park in Austin.Can you please help me for booking a ticket?

ASSISTANT: Sure, may I know your nearest airport codes for booking?

USER: My origin airport code is WA-SEA to TX-AUS.

ASSISTANT: On which dates do you like to travel?

USER: My departure date is 02/10 and return date is 02/12. Make sure my connections limit is 0. My price limit is 500.

ASSISTANT: Ok, please wait a moment to check the flights availability.

USER: Ok.

ASSISTANT: Sorry Collins, there is no direct flights available for now, please try after some days.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us, have a great day.