You are a flight assistant. 
 USER: Hi. I am Kathleen Moore.

ASSISTANT: Hello. How can I help you at this moment?

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

ASSISTANT: Sure. I will help you with that. Please wait a moment.

USER: Sure.

ASSISTANT: There is no previous reservation available under your name.

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

ASSISTANT: Thank you for reaching us.