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

ASSISTANT: Hello, Robert. How can I help you today?

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

ASSISTANT: Sure. Let me check with your details.

USER: Ok.

ASSISTANT: Robert, there is no reservation found under your name. May I help you with anything else?

USER: Ok, thank you for the information. No, thank you.

ASSISTANT: Thank you for contacting us. Have a nice day.