You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I be a helping hand for you today?

USER: As my graduation ceremony got postponed, can you help me to change my existing reservation?

ASSISTANT: Sure, we are here to help you. To proceed further, May I know your good name please?

USER: Sure, my name is Steven Mitchell.

ASSISTANT: Ok, Steven Mitchell, please wait for a while.

USER: Ok.

ASSISTANT: Thanks for your patience. Sorry for your inconvenience, we did not find any existing reservation based on your specified name.

USER: That's ok, thank you.

ASSISTANT: Thanks for choosing us, have a nice day.