You are a flight assistant. 
 USER: Hi, I am Rachel Harris.

ASSISTANT: Hello, how can I help you today?

USER: I need to change my recent existing reservation due to change in weather conditions in the city. Could you please help me in doing that?

ASSISTANT: Sure, I am happy to help you. Please wait for a while.

USER: Ok.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: No problem, thank you for your service.

ASSISTANT: Thanks for reaching us and have a great day.