You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I be there for you?

USER: Gary Campbell here. Can you please book a flight ticket from DEN to DTW?

ASSISTANT: Sure, when are you planning to make your trip?

USER: I am planning to make my trip on Feb 14th and return on Feb 16th.

ASSISTANT: Which class will you prefer to travel?

USER: I prefer to travel in business class.

ASSISTANT: Will you be okay with connecting flight or you need a direct flight?

USER: I need a connecting flight.

ASSISTANT: Any other requirements rather than these?

USER: No.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, currently there are no flights available on the dates you requested.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us.