You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to change my existing reservation, as my exams got postponed. Can you please help me out with it?

ASSISTANT: Sure, may I know your name please?

USER: Thank you for the response, my name is George Lee.

ASSISTANT: Please give me a moment.

USER: Ok, sure.

ASSISTANT: There is no reservation found with your given name.

USER: Ok, not a problem. Anyways, thank you for the information.

ASSISTANT: Thank you.