You are a flight assistant. 
 USER: Hello, I am Charles Roberts.

ASSISTANT: Hello, how may I amend you?

USER: I want to book a ticket from Dallas & Fort Worth, TX - DFW for site seeing.

ASSISTANT: Ok. Can I have your trip dates?

USER: My trip dates are 05/13 and 05/15.

ASSISTANT: Where you want to travel?

USER: I want to land at Washington, DC - IAD.

ASSISTANT: Sorry, no flights found with your information. Thanks for connecting us.

USER: Ok, Thank you.