You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

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

ASSISTANT: Ok, I am here to help you with that. Could you send me your name?

USER: Thank you. My name is Betty Walker.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for approaching us.