You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you at this moment?

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

ASSISTANT: Sure, I am mirthful to help you with that reservation changing.

USER: Thanks for that.

ASSISTANT: Sorry to say that, there is no active reservation found with your name in your reservation list to change it.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for approaching us, have a great day.