You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Catherine Adams, can you please help me in booking a flight ticket from DCA to EWR?

ASSISTANT: May i know your travelling dates please.

USER: Sure, my planning dates are from 05/14 till 05/16..

ASSISTANT: I am sorry no flights found on your route.

USER: It's ok, thank you for your information.

ASSISTANT: Thank you.