You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I support you?

USER: Gary Lopez here. I would like to visit AUS to meet my sister, can you help me to book a flight ticket from SFO?

ASSISTANT: Sure, we are mirthful to help you. Can you please provide your preferable dates of journey?

USER: My travelling dates are 15 Feb and 17 Feb.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: Ok, please hold on.

USER: Sure, take your own time.

ASSISTANT: Thanks for waiting, we are unable to provide flights on the given requirements.

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

ASSISTANT: Thank you for contacting us.