You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello\. How may I help you today?

USER: Can you help me in changing my recent reservation, as my exam is postponed?

ASSISTANT: Ok, I am here to help you with that. May I know your good name?

USER: Check under the name Margaret Perez.

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.