You are a flight assistant. 
 USER: Hello, Brenda Williams here.

ASSISTANT: Hello, what can I do for you?

USER: I am planning to visit ORD with my friend, can you please help me in booking a flight ticket from DEN?

ASSISTANT: Sure, May I know your planned dates to travel?

USER: My planning dates are from 12/13 till 12/15.

ASSISTANT: There is no flight available on this route. Sorry for the inconvenience.

USER: That's ok. Thank you for checking.

ASSISTANT: You are welcome.