You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Due to some important work in the office, my manager did not approve leaves, will you help me to change my recent reservation?

ASSISTANT: Sure. May I know your name?

USER: My name is Donna Evans.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for approaching us.