You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

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

ASSISTANT: Sure, please wait for a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry, there is no reservation found on your name in our database to change.

USER: Anyway, thanks for the information.

ASSISTANT: You are welcome.