You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I want to change my exiting reservation, I have some another important work on that dates, can you please change my reservation?

ASSISTANT: Ok, may I know your good name?

USER: Sure, my name is Margaret Wright.

ASSISTANT: Ok. There is no reservation found with your name.

USER: It's ok no problem. Thank you for your information.

ASSISTANT: Most welcome.