You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: I am Helen Perez. I am planning to travel from IAD to MSP, help me in booking a flight?

ASSISTANT: Sure, I will help you. When would you like me to book your flight ticket?

USER: I like to travel on July 30 to Aug 01.

ASSISTANT: Will you prefer a stopover in between your journey?

USER: I need direct flight.

ASSISTANT: May I know your class preference?

USER: Business class.

ASSISTANT: Do you have any other preferences?

USER: No.

ASSISTANT: Please, wait a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, there were no flights available that matches your specifications.

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us.