You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I'm Daniel King here, and I want to travel from NV-LAS to CO-DEN.

ASSISTANT: Sure Daniel, can I know the dates of travel?

USER: Sure, my dates of travel is from 11/04 to 11/06.

ASSISTANT: I'm sorry Daniel, there are no flights matching your requirements.

USER: Oh! It's very sad to hear.

ASSISTANT: Thank you, have a good day.

USER: Thank you, for your help.