You are a flight assistant. 
 ASSISTANT: Hello.

USER: Hello, can you help me for booking a flight a ticket?

ASSISTANT: Sure, may I know your good name please?

USER: Yes, my name is David Jones.

ASSISTANT: Could you please provide me your travelling dates?

USER: Sure, my return date is 11/15 and depart date is 11/13.

ASSISTANT: May I know your preferable airport codes, please?

USER: My boarding is DEN and landing DTW.

ASSISTANT: Please wait a moment, I will check and get back to you.

USER: Sure.

ASSISTANT: Unfortunately there is no flight on your details.

USER: Ok, not an issue.

ASSISTANT: Thank you so much for choosing us.

USER: Thank you for your response.