You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Anthony Martin here. There is a postponement of our meeting, so could you change my existing reservation?

ASSISTANT: Ok, please wait a minute.

USER: Ok.

ASSISTANT: Martin, there are no active reservations found under your details.

USER: That's ok.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your help.