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

ASSISTANT: Hello, How can I help you?

USER: I am planning to meet my uncle at Seattle, WA - SEA, can you please book a flight ticket from Chicago, IL - ORD?

ASSISTANT: Sure, May I know the travel dates?

USER: My travelling dates are 10/21 to 10/23.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for opting us.