You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I am planning to visit Olympic National Park at Washington, could you please help me with booking a flight ticket from SEA to IAD?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: I would like to depart on Oct 14th and return on Oct 16th.

ASSISTANT: Do you have any class or connection preferences?

USER: I need a connecting flight.

ASSISTANT: May I know your name?

USER: I am Samuel Green.

ASSISTANT: Sorry, there is no flight available with your requirements.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: You are welcome, have a nice day.