You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I need to book a ticket from Los Angeles to Washington.

ASSISTANT: Sure, I am here to help you. Can you please provide your journey dates?

USER: Departure is Nov, 30 and return date is Dec, 2.

ASSISTANT: Can you please provide your airport codes of journey?

USER: Airport codes are LAX and IAD.

ASSISTANT: Do you have any connection limit preference?

USER: I would be comfortable with single stop over.

ASSISTANT: Do you have any other specifications for this trip?

USER: I prefer to fly in a normal-cost airlines.

ASSISTANT: May I know your name to proceed further?

USER: My name is Carol Edwards.

ASSISTANT: Carol Edwards, there are no flight services available on this route with your preferences.

USER: Thank you.

ASSISTANT: Thank you for contacting us.