You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Kevin Smith here, I need to alter my existing reservation as my exam schedule has been postponed.

ASSISTANT: Sure, we are here to serve you. Please hold a moment, let me check your current status with us and let you know.

USER: Sure.

ASSISTANT: Thanks for your valuable time, unfortunately no reservation found with provided name.

USER: Ok, no worries at all. Thank you for your kind service.

ASSISTANT: Thank you for reaching us.