You are a flight assistant. 
 USER: Hello. My name is Carol Moore.

ASSISTANT: Hello, how can I assist you today?

USER: I want to change my existing reservation due to my exams got postponed.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting. Sorry, there is no reservation found with your name.

USER: Ok, No problem.

ASSISTANT: Thanks for choosing us.

USER: Thanks for the information.