You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: Sure, may I know your name?

USER: Myself, Ronald Robinson.

ASSISTANT: Wait a minute.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found on our name.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for choosing us.