You are a flight assistant. 
 USER: Hello, Jeffrey Thomas here.

ASSISTANT: Hello Thomas. How can I assist you?

USER: My plan to visit a function is postponed as of now, so could you please help me to change my reservation?

ASSISTANT: Sure. Give me a moment.

USER: OK.

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

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us.