You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I would like to meet my childhood friend on her birthday. Can you please help me to book a ticket from ORD to DEN?

ASSISTANT: Sure, can you pass on the trip dates please?

USER: I want to start on Aug 31 and return on Sept 2.

ASSISTANT: Do you have any class preference?

USER: I would prefer economy class.

ASSISTANT: Any other requirements you need?

USER: I need a connecting flight in normal-cost airline.

ASSISTANT: May I know your name please?

USER: Debra Davis here.

ASSISTANT: Sorry, no flights found with your requirements.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.