You are a flight assistant. 
 USER: Hi, I am Carolyn Clark.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to change my existing reservation as my plan to go for a holiday trip got postponed. Could you please change my reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found on your name in our database.

USER: Ok, not an issue. Thanks for the information.

ASSISTANT: Thank you for opting us.