You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I have booked a flight ticket in last month for a vacation and now I heard that there is a heavy snowfall in Charlotte so, I want to change my existing reservation.

ASSISTANT: Will you please provide your name, that can be helpful to check your reservation.

USER: Sure, I am Linda Nelson.

ASSISTANT: Please give me a moment. Unfortunately, there is no reservation found under your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Welcome, have a great day.