You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Due to inconvenience of my work, I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, may I know your name please?

USER: My name is Richard Evans.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

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

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for opting us.