You are a flight assistant. 
 USER: Hi. I am Emily Lee.

ASSISTANT: Hello, how may I serve you today?

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.

USER: Thank you.

ASSISTANT: Please wait for a moment, while I search for your reservation.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

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

ASSISTANT: Thank you for reaching us, we hope see you again.