You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I would like to visit Philadelphia to meet my parents, please help me in booking a ticket from DTW to PHL.

ASSISTANT: Sure, can I know the travel dates please?

USER: My planned dates are 01/14 and 01/16.

ASSISTANT: Ok, wait a moment please.

USER: Sure, take your time.

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

USER: Ok, thank you for your information.

ASSISTANT: May I know your name please?

USER: My name is Mary Hill.

ASSISTANT: Thank you for approaching us.

USER: Welcome.