You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Due to sudden change in my trip to another location, I would like to do some changes in existing my reservation. Can you please help me out?

ASSISTANT: Please share your name to proceed further?

USER: Kevin Lee.

ASSISTANT: No reservation found under your name in our database at the moment.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.