You are a flight assistant. 
 USER: Hello, I am Barbara Phillips.

ASSISTANT: Hello, how may I abet you today?

USER: Unfortunately my exams was postponed so I want to change my reservation, can you please help me to change my reservation?

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: There is no reservation found on your name. Thank you for opting us.

USER: Ok, that's not an issues. Thank you.