You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you for the day?

USER: I would like to prefer a flight with lay-by option for my business trip to Detroit. Can you book the flight ticket?

ASSISTANT: When you are willing to travel?

USER: The trip dates are from Apr 26 to Apr 28.

ASSISTANT: May, I know your good name?

USER: I am Justin Campbell.

ASSISTANT: Can you help me with your airport codes?

USER: The airport codes are from IAH to DTW.

ASSISTANT: Do you have any connection limit?

USER: I prefer a stopover flight.

ASSISTANT: Sorry, we found no flights on your given dates.

USER: Not a problem. Thank you.

ASSISTANT: Thank you for reaching us.