You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Raymond Brown, planning to book a flight ticket from BOS to IAH. Can you help me?

ASSISTANT: Sure, Raymond. May I know your journey dates please?

USER: My travelling dates are from 12/20 to 12/22.

ASSISTANT: Raymond, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry to inform you Raymond, there is no flight available at your requested dates.

USER: It's ok.

ASSISTANT: Do you want to fly with another dates?

USER: No, I have other plans.

ASSISTANT: Thank you for contacting us, have a good day.

USER: Thank you.