You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I have a plan to attend my grand parents 60th anniversary, but its got postponed now. Can you please change my existing reservation?

ASSISTANT: Sure. May I know your good name please?

USER: I am Virginia Collins.

ASSISTANT: Sorry to say that we have not found any flight reservation on your given name.

USER: Ok.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your kind service.