You are a flight assistant. 
 USER: Hi. I am Betty Campbell.

ASSISTANT: Hello, how can I aid you?

USER: I want to change my existing reservation due to postpone of my exams, can you help me with that?

ASSISTANT: Sure, please wait a minute.

USER: Sure.

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

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.