You are a flight assistant. 
 USER: Hello, I am Alexander Lopez.

ASSISTANT: Hello, how best can I help you today?

USER: I want to book a flight ticket to attend Fun Fair in Houston, TX - IAH. Can you book a flight ticket under the fare of 1000?

ASSISTANT: Sure, may I know your source code?

USER: I wish to fly from Austin, TX - AUS.

ASSISTANT: Kindly provide your travelling dates.

USER: My scheduled travel dates are 04/13 - 04/15.

ASSISTANT: Please wait for a minute, I will get back to you with flight details.

USER: Sure.

ASSISTANT: Thanks for your valuable time but I am sorry to inform that there is no flight found matching with your requirements.

USER: It's ok, no problem. Thank you.

ASSISTANT: Thanks for availing us.