You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you for this moment?

USER: I wan to book a flight on the route from Washington DCA to Boston BOS, can you help me?

ASSISTANT: Ok, may I know your dates of journey please?

USER: Ok, I will be travelling from 02/17 to 02/19 in the next month.

ASSISTANT: Please wait for a moment to check for the availability of a ticket.

USER: Sure.

ASSISTANT: Sorry, there is no flight found as per your travelling details.

USER: Ok, no issues with it.

ASSISTANT: May I know your name please?

USER: Ok, my name is Patrica Lee.

ASSISTANT: Ok, thank you for contacting us.

USER: Thank you for helping me.