You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Donna Gonzalez.

ASSISTANT: Ok.

USER: My exam got postponed due to bad weather, so please help me in changing my existing reservation.

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, no reservation found with your name.

USER: Not an issue, thank you for your information.

ASSISTANT: Thank you for opting us.