You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Kimberly Robinson want to change my existing reservation as my exams prepone, can you please aid in that?

ASSISTANT: Sure. Please wait for a moment.

USER: Sure.

ASSISTANT: We did not found any reservation on your good name.

USER: Ok, no problem.

ASSISTANT: Thanks for choosing us.

USER: Thank you for sharing your valuable information.