You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I am William Baker. I would like to book a flight ticket from DTW and LAS to meet my uncle.

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: My travelling dates are May 11 and May 13.

ASSISTANT: Do you have any class or time preferences?

USER: I need a economy class.

ASSISTANT: Do you have any connection or airline preferences?

USER: I need a connecting flight.

ASSISTANT: Do you have any other preferences?

USER: I want to return in the afternoon.

ASSISTANT: Sorry, there is no flight available with your requirements.

USER: No worries, thank you for the information.

ASSISTANT: You are welcome, have a nice day.