You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: I need to change my recent existing reservation due to postpone of my document verification in office. Can you help me in this?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: May I know your good name please?

USER: I am Alexander Edwards.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name.

USER: Ok. Thanks for the information.

ASSISTANT: Thank you for reaching us.