You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Nicholas Smith, I need to book a flight ticket to IAD from SFO.

ASSISTANT: Ok, I will help you with that. May I know the travel dates please to check the flights availability?

USER: Thank you, my travelling dates are 06/29 and 07/01.

ASSISTANT: Sorry, there is no flight available on that date.

USER: Not a problem, anyway thank you for the help.

ASSISTANT: Thank you for connecting with our agency.