You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

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

ASSISTANT: Sure, please share me your good name.

USER: I am David Brown.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservation found on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for availing us.