You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

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

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Mar, 20 and Mar, 22 are my travel dates.

ASSISTANT: Do you have any specifications about flight connections?

USER: I would prefer to single connection.

ASSISTANT: Do you have any preferences about class?

USER: No, thanks.

ASSISTANT: Please mention your name.

USER: Deborah Baker here.

ASSISTANT: There are no flights found under your preferable details.

USER: That's ok, thank you.

ASSISTANT: Welcome, have a great day.