You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am William Clark, want to travel from PHX to SEA.

ASSISTANT: May I know your travelling dates?

USER: My travelling dates are from 07/10 to 07/12.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: It's ok, thank you.

ASSISTANT: Most welcome.