You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Nicole Campbell. I would like to attend for the celebrations of Groundhog Day at Denver, Can you reserve me a flight ticket from IAD?

ASSISTANT: Sure, can you share your journey dates?

USER: I am planning to depart on Feb 01 and return on Feb 03.

ASSISTANT: May I know your landing airport code?

USER: I have to land at DEN.

ASSISTANT: Do you have any preferences?

USER: I need a stopover in between my journey.

ASSISTANT: Sorry, there is no flight on your given dates.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.