You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Nancy Davis here.

ASSISTANT: How may I assist you today?

USER: Can you make changes in my existing reservation?

ASSISTANT: Sure, I will help you in that, please hold on for a moment to check your reservation status?

USER: Sure, take your time.

ASSISTANT: Davis, there is no any active reservation with your name in my database.

USER: It's ok, thanks for your information.

ASSISTANT: It's my pleasure.