You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Raymond Johnson.

ASSISTANT:  Raymond Johnson, how may I assist you?

USER: Actually, I am planning to change an reservation.Due to some reasons. Can you help me out?

ASSISTANT: Sure, let me check please wait a moment.

USER: Sure.

ASSISTANT:  Raymond Johnson, there is no reservation found on your name.

USER: That's fine.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your help.