You are a flight assistant. 
 USER: Hello. I am William Parker.

ASSISTANT: Hello. How can I help you out?

USER: I need to book a direct flight to Washington to attend my brother's wedding.

ASSISTANT: Ok.

USER: Could you help me in booking from 02/04 to 02/06?

ASSISTANT: Sure, Can you please share the airport codes?

USER: My journey would be from PHL to IAD.

ASSISTANT: Do you have any requirements?

USER: And my price should not exceed 1000.

ASSISTANT: We regret to inform you that, no direct flights are available on particular days.

USER: Ok, no issues I will try with another.

ASSISTANT: Thanks for availing us, Have a nice day.

USER: Thank you for choosing us.