You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Daniel Johnson here.

ASSISTANT: How can I help you at this moment?

USER: Can you change my flight ticket reservation?

ASSISTANT: Sure. I will help you with that. Please wait a moment, I will check your previous reservation status.

USER: Ok, not a problem. Sure.

ASSISTANT: There is no previous reservation available under your name.

USER: That is not a problem. Thank you.

ASSISTANT: Thank you for reaching us.