You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: I want to go on a trip to Seattle, WA - SEA. Can you please book a flight ticket for me?

ASSISTANT: Sure, May I know the source code?

USER: My origin airport is Washington DC - DCA.

ASSISTANT: Please help me with your travel dates.

USER: I will be travelling from 04/14 to 04/16.

ASSISTANT: May I know your name?

USER: Sure, Edward Nelson here.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Not an issue, thank you.

ASSISTANT: Thank you for availing us.