You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Can you please change my recent reservation due to heavy snowfall?

ASSISTANT: Sure, I will help you to change your reservation. Please mention your name.

USER: Thank you. My name is Mary Parker.

ASSISTANT: Sorry, no reservation found on your name to change your reservation.

USER: That's Ok, thanks for your time.

ASSISTANT: Welcome, have a nice day.