You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. How best I can serve you today?

USER: Please make a reservation with the name of Mary Allen to Las Vegas.

ASSISTANT: Sure, can you please forward your journey dates?

USER: I want to travel on Aug 12 and return on Aug 14.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Please let me know your boarding airport code.

USER: I want to board from IAD,.

ASSISTANT: Do you prefer any stopover in between journey?

USER: Yes, I prefer a stopover.

ASSISTANT: Is there any more specifications?

USER: I want to return in the afternoon.

ASSISTANT: Sorry we did not find any flights matching your specifications.

USER: Not an issue, thank you for your information.

ASSISTANT: Thank you for choosing us.