You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: Can you please book a flight ticket from IAD to DTW?

ASSISTANT: Sure, I am glad to help you.

USER: Thank you.

ASSISTANT: When are you planning to start and return?

USER: I have planned my travel dates as Nov 10 and Nov 12.

ASSISTANT: Ok, help me with your class preference.

USER: Sure, I would prefer business class to travel.

ASSISTANT: Can I have your name please?

USER: Sure, myself Amy Garcia.

ASSISTANT: Is there any other concerns?

USER: Yes, I am looking for single connecting flight so please check with that.

ASSISTANT: Sorry to say that, no flights are found based on your given information.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you for choosing us.

USER: Most welcome.

ASSISTANT: Have a nice day.