You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, may I know your name please?

USER: I am Stephen Williams.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

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

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for opting us.