You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my reservation due to postponed of my exams, so please help me in changing.

ASSISTANT: Sure, I am here to assist you. May I know your name?

USER: Sure, I am Emily Anderson.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thank you for your time, No reservation was found on your given name.

USER: No issues, thank you.

ASSISTANT: Thank you for choosing us.