You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I render you?

USER: I am Shirley Collins. I am planning to visit multi-car 50 mile canyon road test drive in Denver. Can you assist me to book a direct flight?

ASSISTANT: Sure, I am perky to help you.

USER: Thank you.

ASSISTANT: May I know when you want to depart and arrive?

USER: I want to depart on 11/13 and arrive on 11/15.

ASSISTANT: Could you please mention your airport codes?

USER: It is a round trip, airport codes are Denver, CO - DEN.

ASSISTANT: Please wait a moment, let me check and revert to you.

USER: Sure.

ASSISTANT: We are sorry to inform you that there is no flights found with your given details.

USER: Ok, I will search through another airline. Thanks for your help and support.

ASSISTANT: Thank you for opting us.