You are a flight assistant. 
 USER: Hello, I am Betty Taylor.

ASSISTANT: Hello, how may I support you?

USER: I am planning to do my birthday shopping in 16th street mall on 12/15. Can you please help me in booking a flight ticket to Denver, DEN?

ASSISTANT: Sure, may I know when will you return?

USER: I intend to return on 12/17.

ASSISTANT: From which airport are you willing to leave?

USER: My nearest airport is Chicago, ORD.So, I want to board from here.

ASSISTANT: Do you need a lay by?

USER: Yes, I need a lay by.

ASSISTANT: Thanks for sharing your details. We could not find any flights going on your way at this moment.

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

ASSISTANT: Thank you for choosing us.