You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you please reserve me a flight ticket from CLT to SEA?

ASSISTANT: Sure, I am glad to help you with that. Can you please provide your preferable dates of travelling?

USER: My travelling dates are Mar 16 and Mar 18.

ASSISTANT: Do you need any layovers between your trip?

USER: I need a lay by in between my journey.

ASSISTANT: Is there any other requirements?

USER: My return time is evening.

ASSISTANT: May I know your name?

USER: I am Helen Thomas.

ASSISTANT: Thanks for providing all your details. We deeply regret to inform that there are no flight going on your way on the dates you requested.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us.