You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I want to visit National Gallery art in Washington, can you help me in booking a ticket?

ASSISTANT: Sure, I will help you to book your flight. If you know your airport codes then please let me know.

USER: My airport codes are from BOS to DCA.

ASSISTANT: On which dates you are willing to travel?

USER: My travel dates are 05/19 and 05/21.

ASSISTANT: Ok. Please wait a while, I will get back to you.

USER: Ok.

ASSISTANT: There is no flight available on these dates. May I know your name for our agency documentation?

USER: I am Anna Phillips.

ASSISTANT: Thank you Anna to approach us.

USER: No problem, thank you for checking.

ASSISTANT: Most welcome.