You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you right now?

USER: Owning to an emergency I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, I can help you with that one.

USER: Thank you.

ASSISTANT: Can I have your name for checking purpose?

USER: Sure, my name is Alexander Nelson.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT:  Thank you for waiting, there is no reservation found for the user name in our data base.

USER: Ok, not an issue. Thank you for checking.

ASSISTANT: You are most welcome and have a great day, thank you for reaching us.