You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you today?

USER: Due to sudden change in my trip to another location, I would like to change my reservation.

ASSISTANT: Sure, may I know your good name?

USER: Can you please help me out with changing? My name is Frank Nelson.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: No problem, thank you.

ASSISTANT: Thank you.