You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I aid you today?

USER: I am David Hills, I want to book a flight ticket to visit Heard Museum at Phoenix. Please help me out.

ASSISTANT: Sure. Let me know your travelling dates.

USER: My travelling dates are from 12/26 to 12/28. I need a direct flight.

ASSISTANT: Please provide your airport codes.

USER: I want to fly from MA- BOS to AZ- PHX.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no direct available on your specified dates.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you.