You are a flight assistant. 
 USER: Hello, I am Samantha Walker.

ASSISTANT: Hello, how can I help you?

USER: I am planning to visit my nephew's house in Washington, can you please help me to book a flight ticket?

ASSISTANT: Sure. Can you please provide the travelling details?

USER: My source is at PHX and destination is at IAD.

ASSISTANT: Please share your journey dates.

USER: I need a direct flight. My journey starts from 11/05 and 11/07.

ASSISTANT: Thanks for the information. We did not have any direct flights matching your criterion.

USER: Ok, no issues. Thanks for your service.

ASSISTANT: Thanks for approaching us.