You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Patrick Hernandez.

ASSISTANT: How can I assist you today?

USER: Can you help me in booking the ticket from AUS to DFW?

ASSISTANT: Sure, can you please share your travel dates?

USER: My planning dates are from 12/10 to 12/12.

ASSISTANT: Let me check for the availability of flight.

USER: Ok.

ASSISTANT: Patrick, I am sorry to inform you that there is no flight available at your requested dates.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.