You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I lend a hand to?

USER: Can you please help me to change my reservation?

ASSISTANT: Sure, I am here to help you for this. May I know your name please?

USER: I am Shirley Williams.

ASSISTANT: Please wait for a while, let me check your reservation status in our records.

USER: Sure.

ASSISTANT: Sorry to inform you, no reservation is found with your credentials.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you very much for approaching our agency.