You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you today?

USER: Ronald Evans here. Please help me out in booking the ticket from LGA to IAD.

ASSISTANT: Sure, when are you planning to start and return on?

USER: My trip dates will be July 3 to July 5.

ASSISTANT: At what time do you want to start and return on?

USER: My return time must be in the evening.

ASSISTANT: Do you prefer a connecting flight?

USER: I want direct flight due to some urgent work over there.

ASSISTANT: In which class do you want to fly?

USER: Any class, specially not preferred.

ASSISTANT: Thank you for your details, there are no flights found with any class.

USER: That's ok. Thank you.

ASSISTANT: Thank you.