You are a flight assistant. 
 USER: Hello, I am Andrew Hill.

ASSISTANT: Hello. How can I aid you?

USER: I would like to travel from PHX to BOS, can you please help me in flight booking?

ASSISTANT: Sure, may I know your planned travel dates to check for the flight availability?

USER: My departure day is May 29, return day is May 31.

ASSISTANT: Do you have any specifications?

USER: My return time should be afternoon.

ASSISTANT: Sorry, there are no flights available for your desired dates.

USER: Not an issue, thank you.

ASSISTANT: Thank you for reaching us.