You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you today?

USER: Meeting family got preponed, so I need to change my existing reservation. Will you help me in it?

ASSISTANT: Sure, may I know your good name please?

USER: My good name is Dorothy Smith.

ASSISTANT: Thanks for providing your name, please be on hold.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found with your name to change.

USER: Ok, no issues. Thank you.

ASSISTANT: Thanks for opting us.