You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I'm Robert Miller. I am planning to reserve a plane ticket from OAK to OAD, could you please help me out?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: Sure, I am willing to travel on these dates that is from 07/13 to 07/15.

ASSISTANT: Sorry for the inconvenience, there is no flight available on your requested dates.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for approaching us.