You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am Kenneth Mitchell, Want to travel from IAD to DCA. Please help me.

ASSISTANT: Sure, I am here to help you with that. Can I know your travelling dates?

USER: My travelling dates are from 06/13 to 06/15.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry to inform you that, there are no flight's available based on your travelling dates.

USER: That's fine, thank you.

ASSISTANT: Thank you for choosing us.