You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I oblige you today?

USER: Myself Lisa Miller. I want to change my travel dates in my previous reservation so can you please help me with that?

ASSISTANT: Sure, please wait for a moment.

USER: Ok, thank you.

ASSISTANT: Thank you for waiting, there is no active reservation found with the given  name.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you.