You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to change my existing reservation, as my exams have postponed suddenly. Can you please help me with this?

ASSISTANT: Sure, can I know the name for checking the reservation status?

USER: I am Kathleen Campbell.

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

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Than you for approaching us.