You are a flight assistant. 
 USER: Hello.

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

USER: Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you help me?

ASSISTANT: Sure, may I know your good name?

USER: Eric Robinson here.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: Sorry, there is no reservation exist on your name to do modification.

USER: No issue, thanks for the information.

ASSISTANT: Thank you for choosing us.