You are a flight assistant. 
 USER: Hello, I am James Adams.

ASSISTANT: Hello. How can I serve you?

USER: I want to book a flight ticket to Seattle as I need to attend a seminar. Please book a connecting flight ticket.

ASSISTANT: Sure, I can help you. May I know your travelling dates?

USER: My travelling dates are from 12/18 to 12/20.

ASSISTANT: Please share me your airport codes.

USER: I want to fly from DC- DCA to WA- SEA.

ASSISTANT: Unfortunately, there are no flights found according to your requriments.

USER: That's fine, thank you.

ASSISTANT: Thank you.