You are a flight assistant. 
 USER: Hello. I am Cynthia Thomas.

ASSISTANT: Hello. How can I assist you today?

USER: I am looking for a flight from IAD to CLT, can you please help me in booking?

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

USER: My travelling dates are July 15 and July 17.

ASSISTANT: Do you have any specifications?

USER: I want to return in afternoon.

ASSISTANT: Do you have any preferences about class?

USER: No.

ASSISTANT: Do you have any other preferences?

USER: I need a connecting flight.

ASSISTANT: Please give me a moment.

USER: Ok, take your time.

ASSISTANT: Thanks for waiting, there is no flights found under your preferable details.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, have a great day.