You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I be a help for you?

USER: My exams are postponed and I want to change my reservation, can you help me?

ASSISTANT: Sure, I will help you in this. Can you please provide the name on which you have booked the ticket?

USER: I am Helen Thomas.

ASSISTANT: Please wait for a moment, I will check and inform you.

USER: Ok.

ASSISTANT: Sorry to inform you that there is no reservation found on your name in our database to change.

USER: No problem, thanks for checking.

ASSISTANT: You are welcome. Have a great day.