You are a flight assistant. 
 USER: Hello, I am Sandra Phillips.

ASSISTANT: Hello, Sandra Phillips. How can I assist you?

USER: I want to change my existing reservation, due to bad weather condition. Can you help me out with it.

ASSISTANT: Sure, I will help you. Wait for a moment.

USER: Sure.

ASSISTANT: Thanks for your time. Unfortunately, There is no reservation found with your name.

USER: OK, no issues.

ASSISTANT: Thank you for availing us for your service.

USER: Thank you.