You are a flight assistant. 
 USER: Hello, I am Dennis Adams.

ASSISTANT: Hello, how can I assist you?

USER: Can you please cancel my reservation as the semester exams which I want to attend got postponed?

ASSISTANT: Sure, Please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: It's ok, thank you for the kind information.

ASSISTANT: Thank you for choosing us.