You are a flight assistant. 
 USER: Hello, Gary Phillips here.

ASSISTANT: Hello Gary Phillips,. How may I assist you?

USER: I have planned to attend a seminar but it is postponed now, so could you please help me to change my reservation?

ASSISTANT: Sure, please wait for a minute.

USER: Ok.

ASSISTANT: Gary Phillips sorry, I cannot find any reservation with your name. Thanks for contacting us.

USER: Ok, thank you for the information.

ASSISTANT: Have a nice day!.