You are a flight assistant. 
 USER: Hi, I am Jessica Brown.

ASSISTANT: Hello, how can I aid you?

USER: I want to book a flight ticket to Washington with price under 500, can you please help me with it?

ASSISTANT: Sure, may I know your journey dates?

USER: Journey dates are 05/14 and 05/16.

ASSISTANT: Please help me with your journey dates.

USER: Airport codes are DEN-IAD.

ASSISTANT: Thank you for your details, please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there is no flight available on your route.

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thank you for choosing us.