You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I want to travel from HOU to AUS. Can you help me to book a flight ticket?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: I want to travel in the flight on Sept 16 and Sept 18.

ASSISTANT: Would you like to travel in a connecting flight or a direct flight?

USER: I am looking for a direct flight.

ASSISTANT: Do you have any class preference?

USER: I prefer to travel in normal-cost airline.

ASSISTANT: May I know your good name please?

USER: Daniel Baker.

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

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you for reaching us.