You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you?

USER: Can you help me to book a flight ticket from LAS to DTW?

ASSISTANT: Sure, may I know the travelling dates?

USER: My planning dates are 03 to 05 of Nov.

ASSISTANT: Do you have any connection limit?

USER: I am looking for a single connection flight.

ASSISTANT: Is there any other requirements?

USER: I prefer to depart in the evening.

ASSISTANT: May I know your name?

USER: I am Alexander Evans.

ASSISTANT: Sorry, no flights found with your chosen dates.

USER: It's ok, not a problem, thank you.