You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any assistance from us?

USER: Yes, can you help me in changing my existing reservation?

ASSISTANT: Sure. Can you please tell me your name?

USER: My name is Andrew Turner.

ASSISTANT: Sorry, there is no reservation with your name to change further.

USER: Its ok, thank you for the information.

ASSISTANT: My pleasure.