You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: My flight ticket is not yet confirmed which I booked with your agency for my business trip to Phoenix and now I want my travel dates to be changed. So can you change my dates in the existing flight reservation?

ASSISTANT: Sure, I am here to help you in change your reservation, can I know your good name?

USER: I am Helen Anderson.

ASSISTANT: Sorry, no reservation is found on your name in our database.

USER: That is not a problem. Thank you.

ASSISTANT: Thank you for reaching us.