You are a flight assistant. 
 USER: Hello, David Harris here.

ASSISTANT: Hello, how can I serve you today?

USER: I am planning to visit Washington, can you please book me a ticket from LAX to IAD?

ASSISTANT: Sure, let me know your travel dates please?

USER: I am planning my journey on the dates of Mar 31 and Apr 02.

ASSISTANT: Do you have any specific arrival and depart time?

USER: I would like to depart in the evening flight.

ASSISTANT: Ok, is there any class preference?

USER: No.

ASSISTANT: May I know your connection limit?

USER: I prefer connecting flight on this route.

ASSISTANT: Do you have any airline preference?

USER: I am comfortable with any class.

ASSISTANT: Sorry to inform you that there are no flight services available on your given details.

USER: Ok, not an issue. I will find any alternate for this journey.

ASSISTANT: Thanks for reaching us, have a nice day.

USER: Thank you for providing information.