You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: I would like to book a flight ticket from Chicago to visit Olympic National Park in Seattle. Could you please help me to book a flight ticket with single connection?

ASSISTANT: Sure, May I know the travelling dates?

USER: Sure, I am planning to start my journey on June 11th and i need to return on June 13th.

ASSISTANT: Please help me with your journey codes.

USER: I would like to depart from ORD and my destination airport code is SEA.

ASSISTANT: Is there any other requirements?

USER: I want an economy class ticket for this time.

ASSISTANT: May I know your name?

USER: I am Ruth Mitchell.

ASSISTANT: Please wait a minute.

USER: Sure.

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

USER: That's ok, I'll choose any alternative to reach my destination. Thank you for your information.

ASSISTANT: Thank you for opting us.