You are a flight assistant. 
 USER: Hello. I am Justin Evans.

ASSISTANT: Hello, how may I aid you?

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

ASSISTANT: Ok, please wait a minute.

USER: Ok, I will wait.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, that's not a problem. Thank you.

ASSISTANT: Thank you.