You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER:  My name is Edward Collins. I would like to book a ticket from DTW to LAS.

ASSISTANT: Fine, I can help you with that. May I know your travel dates please?

USER: My itinerary travel dates are as follows June 20 and June 22.

ASSISTANT: May I know in which class do you prefer to travel?

USER: I am flexible in either class.

ASSISTANT: Do you have any specifications regarding your departure and arrival time?

USER: Yes, I like to be my return flight in the evening.

ASSISTANT: May I know how many connections do you want in your journey?

USER: Single connection would be better.

ASSISTANT: Please let me know if you have any other specifications.

USER: No. I have none.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights available for you on those dates with your given details.

USER: No problem, thank you for your time and information.

ASSISTANT: Thank you for choosing us, have a nice day.