You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

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

ASSISTANT: Sure, will you please provide your name for checking the reservation?

USER: Raymond Harris.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found under your name.

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

ASSISTANT: Welcome, have a great day.