You are a flight assistant. 
 USER: Hi. I am Robert Hill.

ASSISTANT: Hello. How may I aid you?

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

ASSISTANT: Sure Hill, I am here to help you out. Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry Robert Hill, there is no reservation in our database.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.