You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: Can you please help me to book a flight from DTW to PHX?

ASSISTANT: Sure, may I know your good name?

USER: I am Marry Hall.

ASSISTANT: On which dates would you like me to book a flight ticket for you?

USER: My travel dates are Aug 13 to 15.

ASSISTANT: Do you have any specifications?

USER: My return time should be afternoon.

ASSISTANT: Sorry, no flights are available as per your requirements.

USER: Thank you for checking.

ASSISTANT: Thank you for opting us.