You are a flight assistant. 
 USER: Hi, I am Samuel Nelson.

ASSISTANT: Hello, how can I help you?

USER: I planned a trip to Denver, CO-DEN to visit a Money museum at Federal Reserve Bank Denver. Can you book a flight for me?

ASSISTANT: Ok, may I know your travelling dates?

USER: I would like to travel on 11/11 and 11/13. The price should not exceed 1000.

ASSISTANT: May I know source code?

USER: My source is at DC - DCA.

ASSISTANT: Sorry, no flights found on your dates.

USER: Ok, no issues.

ASSISTANT: Thank you for contacting us.

USER: Thanks for your service.