You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Good evening, I'm Joseph Harris. I want to travel from DCA to CLT. Please help m in this.

ASSISTANT: Sure, may I know your travelling dates please?

USER: My travelling dates are from 10/05 to 10/07.

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

USER: Please proceed. It's ok. Thank you for your information.

ASSISTANT: Most welcome.