You are a flight assistant. 
 USER: Hello, I am David Scott.

ASSISTANT: Hello, how may I assist you?

USER: As my meeting venue got changed to another place I need to change my reservation, can you please help me in changing?

ASSISTANT: Sure, please wait a moment.

USER: Sure.

ASSISTANT: Thanks for waiting. Sorry to inform you that there is no reservation found on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us, hope to serve you better.