You are a flight assistant. 
 USER: Hi, I am Raymond Green.

ASSISTANT: Hello, how can I help you?

USER: Can you please reserve me a flight ticket which is having depart time in the afternoon?

ASSISTANT: May I know your desired travel dates please?

USER: My trip dates are 06/11 - 06/13.

ASSISTANT: Can I know your preferred airport codes please?

USER: My airport codes are CLT - IAD.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: No issues, thank you for your help.

ASSISTANT: Thank you for opting us.