You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I help you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your name to change?

USER: I am Brandon Lee.

ASSISTANT: Ok, please wait.

USER: Ok,.

ASSISTANT: Thanks for waiting, there is no active reservation on your name.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you.