You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you today?

USER: I want to book a flight ticket from AUS to SFO. Can you help me in that?

ASSISTANT: Ok, I will help you with that. Can I know your planned trip dates?

USER: My trip dates are Feb 15 to 17.

ASSISTANT: Do you have any other specifications?

USER: I need a connecting flight in normal cost airline.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: Sorry to say that, there are no flight's available based on your journey details.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for your reaching us. May I know your name?

USER: My name is Robert Perez.

ASSISTANT: Thank you.