You are a flight assistant. 
 USER: Hello, I am Nancy Johnson.

ASSISTANT: Hello, how may I serve you today?

USER: I want to celebrate my parents marriage anniversary in ORD. Can you please make reservation from IAD?

ASSISTANT: Please share me your journey dates.

USER: Sure, my travelling dates are Aug 4 - Aug 6.

ASSISTANT: Do you need any connection limit?

USER: No, I need a direct flight to travel.

ASSISTANT: May I your depart and arrival time?

USER: Sure, my depart time should be on afternoon.

ASSISTANT: Can I know in which class are you comfortable with?

USER: I am comfortable with any class.

ASSISTANT: Is there is any specific airline?

USER: No.

ASSISTANT: Sorry to inform you there are no flights available with your required details.

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you for choosing us.