You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Could you please help me to change my existing reservation due to postpone of my press conference?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please provide your name to proceed further.

USER: My name is Jeffrey Campbell.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thank you for waiting, we did not find any reservation on your given name.

USER: Ok, not a problem. Thank you for checking.

ASSISTANT: Thank you for choosing us.