You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: John Allen here. I want to book a flight ticket from DEN to DTW. Can you help me in that?

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you.

ASSISTANT: Please provide your planned travel dates to proceed further.

USER: My trip dates are Aug 25 to Aug 27.

ASSISTANT: Do you have any other preferences?

USER: I need a connecting flight in evening time.

ASSISTANT: Do you want either depart or return time in the evening?

USER: My depart time should be in evening.

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry John we don't have any flight which departs in the evening.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for contacting us, we hope to serve you better next time.