You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I would like to change my reservation as my trip got cancelled, can you please help me out with that?

ASSISTANT: Sure, may I know your name please?

USER: Please check on the name David Evans.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, I will stand by.

ASSISTANT: Sorry to say that, there was no reservation found with your given name.

USER: That's ok, thank you.

ASSISTANT: Thank you for opting us.