You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I serve you?

USER: Can you reserve a flight ticket with the name Christopher Lewis?

ASSISTANT: Ok, For that We need your specified airport codes?

USER: I want to start a new book stall at New York NY-LGA, So I need to start from Houston TX-IAH.

ASSISTANT: Ok, when did you plan to reach New York and return?

USER: I have planned to start on 12/28, my return date is on 12/30.

ASSISTANT: Sorry Lewis, no flights found on your preferred travel dates.

USER: Its ok, thank you for your assistance.

ASSISTANT:  Thanks for choosing us.