You are a flight assistant. 
 USER: Hi. I am Nicholas Hill.

ASSISTANT: Hello, how may I be there for you?

USER: I need to change my existing reservation as my exams got postponed, Can you please help me with that?

ASSISTANT: Sure, please wait for few minutes.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.