You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I would like to celebrate Christmas with my family who are living in Detroit, DTW. Can you book a ticket on 12/24?

ASSISTANT: Sure, please share me your return date?

USER: Sure, I intend to return on 12/26 because I have to attend to college.

ASSISTANT: Can I know your origin code?

USER: I will start from my nearest airport Las Vegas, LAS.

ASSISTANT: Do you have any specifications?

USER: Please check flight with a connection. I can afford an amount of 500.

ASSISTANT: Can I have your name?

USER: I am Elizabeth Miller.

ASSISTANT: Sorry, to say you that there is no flight found with your specifications.

USER: Ok, thank you for your information.

ASSISTANT: Thank you for reaching us.