You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am planning to meet my sister in EWR, could you book a ticket from DCA?

ASSISTANT: Sure, please provide your dates too.

USER: My travel dates are 01/03 and 01/05.

ASSISTANT: May I know your name?

USER: Sandra Taylor here.

ASSISTANT: Sorry for the inconvenience, there is no flight for you.

USER: It's ok. Thank you for helping me.

ASSISTANT: Thank you for reaching us.